What Are the Most Common Antibiotics?

Antibiotics are a common, important group of medicines that treat bacterial infections. Some antibiotics attack or break down the cell walls of bacteria, while others inhibit their protein production. This kills the bacteria or keeps it from reproducing and spreading.

Oral antibiotics are available in liquid, tablet, and capsule form. Topical antibiotics include skin creams, sprays, and ointments. Eye ointments, eye drops, and ear drops are also available. Severe infections may require injected or intravenous antibiotics.

Healthcare professionals prescribe different antibiotics to treat conditions such as strep throat, bronchitis, and inner ear infections. In this case, these infections are moderate to severe and have not improved with other treatments.

Antibiotics do not treat viral illnesses, such as a cold, the flu, or mono.

These drugs are grouped according to their antibacterial activity and chemical structure. Specific antibiotics fight certain bacteria, which makes it important to take the right kind. A healthcare professional may ask for a lab culture test to determine which antibiotics you need.

Read on to learn more about the most common types of antibiotics and which infections they treat. We also explore the common side effects of antibiotics, which can include gastrointestinal problems like nausea, vomiting, and diarrhea, as well as more serious effects.

Here are some types of antibiotics that doctors prescribe most often.

Penicillins

Penicillins are a common treatment for a variety of skin conditions. They also treat middle ear, kidney, and blood infections. Penicillin antibiotics are effective at killing Staphylococci and Streptococci infections. But some bacteria are resistant to penicillin, due to overuse.

Common penicillin antibiotics include:

• phenoxymethylpenicillin
• dicloxacillin
• amoxicillin with clavulanic acid
• ampicillin
• nafcillin
• oxacillin
• penicillin V
• penicillin G

Potential side effects include:

• nausea
• abdominal discomfort
• diarrhea
• headache
• yeast infection
• liver disease

Penicillin may cause allergic reactions, such as rashes, hives, and breathing difficulties.

Some medications that may interact with penicillin include oral contraceptives and the anti-inflammatories aspirin and probenecid.

Cephalosporins

Cephalosporins often treat gonorrhea, pelvic inflammatory disease, and sinusitis. They also treat urinary tract infections (UTIs), epididymo-orchitis, and cellulitis. Often, doctors prescribe cephalosporins to people who are allergic to penicillin.

Common cephalosporin antibiotics include:

• cefaclor
• cefazolin
• cefadroxil
• cephalexin
• cefuroxime
• cefixime
• cefoxitin
• ceftriaxone

Tetracyclines

Tetracyclines are a group of antibiotics with anti-inflammatory properties that can treat several bacterial infections. They commonly treat chest, urethral, and pelvic infections. Tetracyclines also treat inflammatory skin conditions, such as acne, rosacea, and perioral dermatitis.

Common tetracycline antibiotics include:

• doxycycline
• minocycline
• sarecycline

Children under 12 and pregnant or breastfeeding people should not take tetracyclines because they have the potential to stain developing teeth.

They can also cause inflammation or irritation of the esophagus. To prevent this, make sure to take doxycycline while sitting or standing upright, and have plenty of water. Also, it’s a good idea to avoid sun exposure, since doxycycline causes photosensitivity, which can lead to sunburn.

Finally, it’s best to take this type of antibiotic after eating to prevent nausea, vomiting, and diarrhea.

Minocycline has more potential side effects than doxycycline, though it’s less likely to cause photosensitivity. Possible adverse effects of minocycline include drug hypersensitivity syndrome, autoimmune reactions, and dizziness and headache. Also, using it for a long period may cause blue pigmentation of skin and nails.

Medications that may interact with tetracyclines include:

• systemic retinoids, such as acitretin, isotretinoin, and alitretinoin
• diuretics
• lithium
• anticonvulsants
• rifampicin
• celestipol
• oral contraceptives

Macrolides

Macrolides are an antibiotic group with anti-inflammatory and immunomodulatory properties. They can treat strains of bacteria that are resistant to penicillin. They are also a suitable option for people who are allergic to penicillin or cephalosporin.

These antibiotics commonly treat skin, soft tissue, respiratory, and sexually transmitted infections, including chlamydia. Healthcare professionals use them, for example, to treat skin conditions like acne, rosacea, erythrasma, and pityriasis lichenoides.

Types of macrolides include:

• erythromycin
• clarithromycin
• azithromycin
• fidaxomicin
• roxithromycin

Macrolides, especially erythromycin and clarithromycin, can adversely interact with certain medications. Reactions and toxicity are more common in older adults and people with renal or liver dysfunction.

Medications that may interact with macrolides include:

• calcium channel blockers, such as verapamil
• amiodarone
• methadone
• lithium
• amitriptyline
• citalopram
• anticoagulants, including warfarin and dabigatran
• digoxin
• benzodiazepines
• carbamazepine
• cimetidine
• clozapine
• colchicine
• theophylline

Fluoroquinolones

Fluoroquinolones, also called quinolones, can fight bacterial infections that are life threatening or challenging to treat. However, they are linked with antimicrobial resistance, so you shouldn’t take them unless it’s absolutely necessary.

Fluoroquinolones are the first-line treatment for prostatitis, along with severe cases of salmonellosis and shigellosis. Doctors also often use them to treat certain cases of epididymo-orchitis, gonorrhea, and tuberculosis. Sometimes, fluoroquinolones treat urinary, eye, and ear infections.

Types of fluoroquinolone include:

• ciprofloxacin
• ofloxacin
• levofloxacin
• moxifloxacin

For people with renal dysfunction, taking this type of drug may require adjustments to dosages of other medications. And, rarely, fluoroquinolone can cause serious adverse effects, especially in older adults.

Potential side effects include:

• tendon rupture
• aortic aneurysm rupture or dissection
• aortic and mitral regurgitation
• central nervous system excitation and seizures
• QT prolongation
• other cardiac conditions

Sulfonamides

Sulfonamides, also called sulfa drugs, are a type of synthetic antimicrobial that doctors prescribe when first-line treatments are ineffective or contraindicated. The most common type is sulfamethoxazole with trimethoprim, called co-trimoxazole. It treats conditions such as pneumocystis pneumonia and nocardiosis in people with weakened immunity, as well as infections of the lower urinary tract in children.

Types of sulfonamides include:

• sulfamethoxazole with trimethoprim
• sulfasalazine
• sulfacetamide
• sulfadiazine silver

Sulfonamides are unsafe during pregnancy because they increase the likelihood of pregnancy loss.

Potential side effects include:

• jaundice in newborns
• candidiasis
• folate deficiency
• headaches
• anorexia
• hyperkalaemia

Medications that may interact with sulfonamides include:

• warfarin
• sulfonylurea hypoglycemic agents
• phenytoin
• methotrexate

Glycopeptides

Glycopeptide antibiotics treat drug-resistant bacteria and gram-positive infections, including multidrug-resistant Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus, better known as MRSA.

Types of glycopeptides include:

• vancomycin
• dalbavancin
• oritavancin
• telavancin

Below, find answers to common questions about antibiotics.

What is antibiotic resistance?

Antibiotic resistance occurs when bacteria survive or resist antibiotic treatment. Bacteria change and mutate to protect themselves after coming into contact with an antibiotic or other bacteria. Once a type of bacteria is resistant, it passes these genes to other bacteria, which continue to grow. Eventually, they create a new strain of antibiotic-resistant bacteria.

Misusing and overusing antibiotics increases the likelihood of antibiotic resistance. Over time, this may lead to a shortage of medications that can effectively treat common infections.

How can I prevent antibiotic resistance?

To prevent antibiotic resistance, avoid taking antibiotics unless it is essential. Don’t take them for viral infections, such as a cold or the flu. Always follow the instructions from your healthcare professional about how much to take when. To prevent infections, clean your hands and living spaces regularly, and take steps to strengthen your immune system.

Are there any natural antibiotics?

Natural antibiotics include honey, thyme essential oil, and oregano essential oil. Extracts of garlic, cranberry, and myrrh also have antibiotic properties. Several herbs are effective antibiotics, including echinacea, turmeric, and ginger.

Natural UTI treatments include D-mannose and uva ursi, along with green, parsley, mint, and chamomile teas.

You can experiment with different combinations of natural treatments to find out which are most effective for your needs.

Antibiotics kill bacteria and prevent them from multiplying. They are valuable drugs that treat bacterial infections. It’s crucial to use them correctly and follow the healthcare professional’s instructions carefully.

It’s also important to be aware of the potential side effects and interactions of antibiotics. Speak with your doctor if you have any related concerns.

Antibiotics – StatPearls – NCBI Bookshelf

Continuing Education Activity

Antibiotics are common agents used in modern healthcare. This was not always the case. From ancient times, people sought ways to treat those afflicted with infections. Dyes, molds, and even heavy metals were thought to hold promise for healing. Various microorganisms have medical significance, including bacteria, viruses, fungi, and parasites. Antibiotics are compounds that target bacteria and, thus, are intended to treat and prevent bacterial infections. This activity will examine the various classes of antibiotics, their mechanisms of action, bacterial susceptibilities, and potential adverse events.

Objectives:

• Identify the various classes of antibiotic medications.

• Explain the various mechanisms of action of different classes of antibiotics.

• Review the potential adverse effects both of antibiotics in general and class-specific side effects.

• Summarize the monitoring requirements for patients receiving antibiotic therapy.

Access free multiple choice questions on this topic.

Introduction

Antibiotics are common agents used in modern healthcare. This was not always the case. From ancient times, people sought ways to treat those with infections. Dyes, molds, and even heavy metals were thought to hold promise for healing.[1] Various microorganisms have medical significance, including bacteria, viruses, fungi, and parasites. Antibiotics are compounds that target bacteria and, thus, are intended to treat and prevent bacterial infections.

Function

Classification

The pharmacology behind antibiotics includes destroying the bacterial cell by either preventing cell reproduction or changing a necessary cellular function or process within the cell. Antimicrobial agents are classically grouped into two main categories based on their in vitro effect on bacteria: bactericidal and bacteriostatic. Common teaching often explains that bactericidal antibiotics “kill” bacteria and bacteriostatic antibiotics “prevent the growth” of bacteria. The true definition is not so simple. To accurately define each category, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) must be understood. The lowest concentration that inhibits visible bacterial growth at 24 hours is the MIC.[2] The MBC is the concentration of an antibiotic that reduces bacterial density by 1000-fold at 24 hours.[2] 

Bacteriostatic activity is further defined by an MBC to MIC ratio greater than 4, whereas an MBC to MIC ratio less than or equal to 4 is bactericidal.[2] The clinical implications of antibiotic efficacy depend heavily on many factors not limited to: pharmacokinetic and pharmacodynamic principles, the particular bacteria, bacterial load, and site of infection. This is further complicated by the ability of some bacteriostatic antibiotics to exhibit bactericidal activity against particular bacteria. [3] Therefore, bacteriostatic antibiotics also kill bacteria, but the laboratory definition makes it seem as if they do not. For example, a bacteriostatic antibiotic such as linezolid can be bactericidal against Streptococcus pneumoniae.[3] This concept works in reverse, and bactericidal antimicrobials may also be bacteriostatic against certain bacterial strains and conditions. Conflicting data exist as to whether the necessity for bactericidal antibiotics is needed for severely ill or immunosuppressed patients.[3]

Types of Antimicrobial Agents[3]  

Drug Class and Specific Antibiotics

Bacteriostatic

• Glycylcyclines: Tigecycline

• Tetracyclines: Doxycycline, minocycline

• Lincosamides: Clindamycin

• Macrolides: Azithromycin, clarithromycin, erythromycin

• Oxazolidinones: Linezolid

• Sulfonamides: Sulfamethoxazole

Bactericidal

• Aminoglycosides: Tobramycin, gentamicin, amikacin

• Beta-lactams (penicillins, cephalosporins, carbapenems): Amoxicillin, cefazolin, meropenem

• Fluoroquinolones: Ciprofloxacin, levofloxacin, moxifloxacin

• Glycopeptides: Vancomycin

• Cyclic Lipopeptides: Daptomycin

• Nitroimidazoles: Metronidazole

Pharmacokinetics and Pharmacodynamics

Pharmacokinetic (PK) and pharmacodynamic (PD) parameters are used together to maximize the efficacy of antimicrobial therapy through optimization of dosing in patients. Absorption, distribution, metabolism, and excretion are the PK components that affect the antibiotic concentration over time.[4] These processes describe how an antibiotic moves through the body from the time it enters the body until the parent drug or metabolites are removed. PD of an antibiotic describes the drug effect within the body when it reaches the infection target. The main principles that guide PD are the percent of the time the free drug is over the MIC, the amount of free drug area under the concentration to MIC, and the maximum concentration to MIC.[5] 

Bactericidal activity is either concentration-dependent or time-dependent. If an antibiotic displays concentration-dependent killing, for example, fluoroquinolones or daptomycin, the efficacy of bacterial killing increases as the concentration of the antibiotic increases.[6] Penicillins and tetracyclines are time-dependent; therefore, the duration of the effective concentration of these antibiotics determines bactericidal activity. [6]

After an antibiotic is absorbed, the distribution influences the extent of antimicrobial activity. The total amount of drug in the body to serum concentration is the volume of distribution.[5] The level of protein binding will affect the availability of the active drug at the site of infection. If an antibiotic is highly protein-bound, there will be less free drug available for an antimicrobial effect, as seen in patients with hypoalbuminemia.[5] Increased adipose tissue in a patient will increase the volume of distribution if a drug has high lipophilicity properties.[7]

The location of infection is crucial to note because some antibiotics are inappropriate for treating certain infections. In the treatment of meningitis, for example, the penetration of the blood-brain barrier is critical if one wants to achieve therapeutic antibiotic levels at the site of infection to prevent treatment failure.[5]

Issues of Concern

Complications

Adverse Reactions

All medications have the potential for an adverse reaction, and antibiotics are no exception. One in five hospitalized patients has been shown to develop an adverse reaction to an antibiotic, and nearly the same proportion of drug-related Emergency Department visits are due to adverse antibiotic reactions.[8][9] An immune-mediated reaction or hypersensitivity is classified as an allergy.[10] This includes IgE-mediated anaphylaxis and angioedema. Medications often reach harmful levels in the body due to reduced metabolism and elimination, or high dosing regimens can cause toxicity due to supratherapeutic drug levels.[11] If a reaction occurs that is not mediated by the immune system and is unrelated to the drug level; then it is considered a side effect.[11]

The anticipation of adverse events is warranted when initiating antimicrobial therapy. Certain patients are at higher risk, for example, the elderly, patients with multiple co-morbidities, and hospitalized patients.[8] It is important to monitor patients for reactions as many develop over time. Some antibiotics necessitate monitoring drug levels to guide therapy for efficacy and prevention of adverse effects such as vancomycin and aminoglycosides. [12] Renal toxicities may develop if these antimicrobials maintain high trough levels; therefore, monitoring renal function is necessary and measuring drug levels.

Adverse Reactions Associated with Organ Systems

Renal

• Acute tubular necrosis

• Interstitial nephritis

• Renal failure

• Crystallization in renal tubules[11]

Cardiac

• QT prolongation[11]

Hematologic

• Thrombocytopenia

• Leukopenia

• Agranulocytosis

• Abnormal platelet aggregation

• INR increase (often due to drug interactions)[11]

Dermatologic

• Rash

• Erythema multiforme

• Stevens-Johnson syndrome

• Toxic epidermal necrolysis[11]

Neurologic

• Ototoxicity

• Vestibular dysfunction

• Seizure

• Peripheral neuropathy[11]

Other

• Hepatotoxicity

• Myopathy

• Electrolyte abnormalities (i. e., hypokalemia, hypoglycemia)

• Drug-induced fever

• Drug-induced diarrhea[11]

Antibiotic Resistance

The increased use of antimicrobial agents in clinical practice and other industries such as livestock farming has led to bacterial resistance to antibiotic agents. Bacteria have developed mechanisms to promote this resistance to survive.  

The MIC of a bacterial isolate can serve as a metric for bacterial susceptibility to certain antibiotics.[13] A high MIC above the susceptibility threshold to an antibiotic will report as a resistant infection. Bacteria may possess resistance to an antimicrobial agent due to intrinsic or acquired properties. Not all antibiotics are effective against all types of bacteria. If a bacterium does not contain the target for a particular antibiotic, it is known to have intrinsic resistance.[14] Vancomycin, an antibiotic known to target work against gram-positive bacteria, cannot cross the cell wall of gram-negative bacteria. [15] Also, beta-lactam antibiotics require a cell wall to function and, therefore, will not be effective against bacteria such as Mycoplasma species that lack this cellular component.

Bacteria also have the capability to gain resistance through attaining resistance genes from other bacteria or developing a mutation resulting in reduced or elimination of antibiotic efficacy. This type of resistance is known as acquired resistance.[14]

More than one type of bacterial resistance may be present in a bacterial organism. Common resistance strategies are listed here.

Mechanisms of Resistance and Examples

Reducing Intracellular Antibiotic Concentrations

Antibiotic Inactivation

• Enzymatic modification

• Chemical degradation[14][15]

Target Site Alteration

• Mutation of the target site

• Antibiotic modification

• Target site protection

• Elimination of the target site[14][15]

Clinical Significance

Approach to Antimicrobial Therapy

The causative organisms and infection source are not always known when a patient first presents.  Antibiotic therapy is often initiated before an exact infectious disease diagnosis, and microbiological results are available. Antibiotics used in this manner are referred to as empiric therapy. This approach attempts to cover all potential pathogens. When microbiology tests result and antibiotic susceptibilities are known, definitive antibiotic treatment can be tailored to the specific infection etiology.[16]

Prophylactic therapy is used to prevent infections in patients who do not have an active infection. Immunocompromised patients may receive prophylaxis against specific opportunistic pathogens. Prophylactic antibiotics are also used before surgical procedures and traumatic injuries such as open fractures and animal bites.[16]

The severity of potential bacterial infection will determine the level of aggressiveness in antibiotic therapy. For example, in a life-threatening infectious disease such as sepsis, empiric broad-spectrum parenteral antibiotics should be administered quickly after sepsis identification and continued until more information is gathered regarding the etiology and causative bacteria. [12] Empiric antibiotics are used to cover all potential bacteria before culture results. After bacterial cultures are available and have resulted, antibiotics can be deescalated to only what is necessary. This approach is termed directed antibiotic therapy.[16] Often, empiric antibiotics are broad-spectrum, which refers to medications targeting many different bacterial classes (i.e., gram-positive, gram-negative, and anaerobic bacteria). In a simple skin and soft tissue infection that does not require hospitalization, narrower spectrum antibiotics may be given orally.[12]

In addition to the possible source(s) of infection, likely pathogens, and situation urgency, different patient factors merit consideration.[12] Patient age, medication allergies, renal and hepatic function, past medical history, the presence of an immunocompromised state, and recent antibiotic usage need to be evaluated before an antibiotic selection. Many of these patient factors contribute to the pharmacodynamics and pharmacokinetics of antibiotics that will influence dosing to optimize efficacy.

Enhancing Healthcare Team Outcomes

A Word on Antimicrobial Stewardship

In the United States, it has been reported that nearly half of the antibiotics prescribed were incorrect in some way, and almost one-third of antibiotics were deemed unnecessary in hospitalized patients.[17] Appropriate antibiotic use has become a public health issue (CDC 19). The practice of antimicrobial stewardship revolves around the concept of optimizing antimicrobial therapy and reducing adverse events through economically responsible methods.[18] These interprofessional programs work to identify ways to improve patient outcomes. Stewardship programs are increasingly becoming more common to address issues related to antibiotic usage, including combating antimicrobial resistance.

Antibiotic therapy and accompanying stewardship require the effort of an interprofessional healthcare team that includes physicians (MDs and DOs), mid-level practitioners (NPs and PAs), pharmacists, and nursing staff. This includes only using these agents when clinically indicated, targeted therapy based on the susceptibility of the infectious organism, and monitoring of side effects and, where indicated, drug levels. Employing interprofessional strategies with open information sharing can improve therapeutic results with antibiotic therapy and minimize adverse events. [Level 5]

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References

1.

Gould K. Antibiotics: from prehistory to the present day. J Antimicrob Chemother. 2016 Mar;71(3):572-5. [PubMed: 26851273]

2.

Pankey GA, Sabath LD. Clinical relevance of bacteriostatic versus bactericidal mechanisms of action in the treatment of Gram-positive bacterial infections. Clin Infect Dis. 2004 Mar 15;38(6):864-70. [PubMed: 14999632]

3.

Nemeth J, Oesch G, Kuster SP. Bacteriostatic versus bactericidal antibiotics for patients with serious bacterial infections: systematic review and meta-analysis. J Antimicrob Chemother. 2015 Feb;70(2):382-95. [PubMed: 25266070]

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Sy SK, Zhuang L, Derendorf H. Pharmacokinetics and pharmacodynamics in antibiotic dose optimization. Expert Opin Drug Metab Toxicol. 2016;12(1):93-114. [PubMed: 26652832]

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Onufrak NJ, Forrest A, Gonzalez D. Pharmacokinetic and Pharmacodynamic Principles of Anti-infective Dosing. Clin Ther. 2016 Sep;38(9):1930-47. [PMC free article: PMC5039113] [PubMed: 27449411]

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Ambrose PG, Bhavnani SM, Rubino CM, Louie A, Gumbo T, Forrest A, Drusano GL. Pharmacokinetics-pharmacodynamics of antimicrobial therapy: it’s not just for mice anymore. Clin Infect Dis. 2007 Jan 01;44(1):79-86. [PubMed: 17143821]

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Meng L, Mui E, Holubar MK, Deresinski SC. Comprehensive Guidance for Antibiotic Dosing in Obese Adults. Pharmacotherapy. 2017 Nov;37(11):1415-1431. [PubMed: 28869666]

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Tamma PD, Avdic E, Li DX, Dzintars K, Cosgrove SE. Association of Adverse Events With Antibiotic Use in Hospitalized Patients. JAMA Intern Med. 2017 Sep 01;177(9):1308-1315. [PMC free article: PMC5710569] [PubMed: 28604925]

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Shehab N, Patel PR, Srinivasan A, Budnitz DS. Emergency department visits for antibiotic-associated adverse events. Clin Infect Dis. 2008 Sep 15;47(6):735-43. [PubMed: 18694344]

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Gruchalla RS, Pirmohamed M. Clinical practice. Antibiotic allergy. N Engl J Med. 2006 Feb 09;354(6):601-9. [PubMed: 16467547]

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Granowitz EV, Brown RB. Antibiotic adverse reactions and drug interactions. Crit Care Clin. 2008 Apr;24(2):421-42, xi. [PubMed: 18361954]

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Lynch TJ. Choosing optimal antimicrobial therapies. Med Clin North Am. 2012 Nov;96(6):1079-94. [PubMed: 23102478]

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Brauner A, Fridman O, Gefen O, Balaban NQ. Distinguishing between resistance, tolerance and persistence to antibiotic treatment. Nat Rev Microbiol. 2016 Apr;14(5):320-30. [PubMed: 27080241]

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Chen LF, Chopra T, Kaye KS. Pathogens resistant to antibacterial agents. Infect Dis Clin North Am. 2009 Dec;23(4):817-45, vii. [PubMed: 19909886]

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van Duijkeren E, Schink AK, Roberts MC, Wang Y, Schwarz S. Mechanisms of Bacterial Resistance to Antimicrobial Agents. Microbiol Spectr. 2018 Jan;6(1) [PubMed: 29327680]

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Leekha S, Terrell CL, Edson RS. General principles of antimicrobial therapy. Mayo Clin Proc. 2011 Feb;86(2):156-67. [PMC free article: PMC3031442] [PubMed: 21282489]

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Fridkin S, Baggs J, Fagan R, Magill S, Pollack LA, Malpiedi P, Slayton R, Khader K, Rubin MA, Jones M, Samore MH, Dumyati G, Dodds-Ashley E, Meek J, Yousey-Hindes K, Jernigan J, Shehab N, Herrera R, McDonald CL, Schneider A, Srinivasan A., Centers for Disease Control and Prevention (CDC). Vital signs: improving antibiotic use among hospitalized patients. MMWR Morb Mortal Wkly Rep. 2014 Mar 07;63(9):194-200. [PMC free article: PMC4584728] [PubMed: 24598596]

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Cunha CB. Antimicrobial Stewardship Programs: Principles and Practice. Med Clin North Am. 2018 Sep;102(5):797-803. [PubMed: 30126571]

Disclosure: Preeti Patel declares no relevant financial relationships with ineligible companies.

Disclosure: Harrison Wermuth declares no relevant financial relationships with ineligible companies.

Disclosure: Chara Calhoun declares no relevant financial relationships with ineligible companies.

Disclosure: Gregory Hall declares no relevant financial relationships with ineligible companies.

What are antibiotics? – article on the website Aptechestvo, Nizhny Novgorod

Antibiotics are a group of drugs that are used in the treatment of bacterial infections. Bacteria are living microorganisms that, having penetrated into the human body, begin active life and reproduction. The effect of antibiotic therapy is the direct destruction of the pathogen, as well as slowing down the reproduction of pathogens. In connection with these antibacterial drugs are divided into 2 large groups: bactericidal – destroying the bacterium itself, as well as bacteriostatic, inhibiting their growth. In addition, antibiotics have a narrow and broad spectrum of action. Narrow-spectrum drugs destroy the infection selectively, while broad-spectrum drugs destroy most of the microorganisms, including those that benefit humans. What antibiotics to take for the treatment of various diseases should be decided by the doctor after the diagnosis. Taking such drugs at your own discretion is fraught with complications.

Fluoroquinolones

They suppress the activity of enzymes involved in the formation of bacterial DNA, as a result of which the infection dies. The drugs are available in the form of tablets, injections, ophthalmic drops. Indications for appointment:

This group of drugs:

• Ciprofloxacin;

• Ofloxacin;

• Pefloxacin;

• Norfloxacin.

Aminoglycosides

Broad-spectrum agents that kill most types of Gram-negative aerobic and facultative bacteria. The active substance disrupts the process of protein synthesis, as a result of which the pathogen is destroyed and dies.

Aminoglycosides are poorly absorbed when taken orally, so, as a rule, they are prescribed as intravenous or intramuscular injections. Members of this group:

• Amikacin;

• Gentamicin;

• Kanamycin;

• Neomycin;

• Plazomycin;

• Streptomycin.

As a rule, these drugs are used in combination with other antibiotics to treat such infectious diseases:

Tetracyclines

Bacteriostatic antibiotics that retard the growth of pathogenic microorganisms, but do not completely destroy them. As a result, the reproduction of the infection stops, and it gradually dies.

Tetracyclines have a wide spectrum of activity, with pronounced activity against aerobic gram-positive and gram-negative bacteria. Tetracyclines are not prescribed for children under 8 years of age, since long-term use causes a number of serious complications.

The drugs of this group can be prescribed in tablet forms and in the form of injections. For the treatment of ophthalmic infections, ointments are produced, the active substance of which is tetracycline.

Medicines:

• doxycycline;

• minocycline;

• Tetracycline;

• Oxytetracycline.

Diseases for which tetracyclines are prescribed:

Macrolides

They suppress vital activity and prevent the reproduction of anaerobic and aerobic gram-positive bacteria. Preparations of this group are used in the treatment of bronchopulmonary infections, tonsillitis, otitis, scarlet fever, intestinal infections. Medicines that are included in this group:

• Erythromycin;

• Azithromycin;

• Clarithromycin;

• Spiramycin.

Penicilli

A group of antibiotics produced by the fungus Penicillium. Penicilli are active against most Gram-positive and some Gram-negative bacteria. This group of drugs:

• Amoxicillin;

• Augumetin;

• Amoxiclav;

• Flemoxin Slutab.

Cephalosporins

These are bactericidal beta-beta-lactam antibiotics that interfere with cell protein synthesis. There are 5 generations of cephalosporins. The active substance penetrates well into most body fluids, having a pronounced bactericidal effect. Cephalosporins are used for uncomplicated skin and soft tissue infections caused by staphylococcal and streptococcal bacteria. This group of drugs:

• Ceftriaxone;

• Cefodox;

• Cefix;

• Tsepefim.

Bacteria are organisms that do not live long, but in order to restore their population, they multiply rapidly, and, accordingly, quickly mutate, adapting to new living conditions. Microorganisms that survive after taking antibiotics become resistant to them. Their offspring also become immune to a particular drug.

Antibiotic resistance is a common problem of modern man, which causes serious complications. A person who has tried many antibiotics, that is, self-medicated, is at risk for patients with antibiotic resistance. Very often they die before a specialist can pick up a drug that works against a specific pathogen. Therefore, it is important to follow the recommendations of the doctor and take antibacterial agents strictly according to an individual scheme.

8 groups of antibiotics and a list of the best

Contents

• 1 8 groups of antibiotics, a list of the best drugs for fighting bacteria
  • 1.1 Antibacterials: groups and best examples
  • 1. 2 Group of beta-lactam antibiotics 90 014
  • 1.3 Macrolide antibiotic group
  • 1.4 Tetracycline antibiotic group
  • 1.5 Aminoglycoside antibiotic group
  • 1.6 Quinolone antibiotic group
  • 1.7 Glycopeptide group
  • 1.8 Lincosamide group
  • 1.9 Polymyxin group
  • 1.10 Antibacterial drug Azithromycin
  • 1.11 Antibacterial drug Amoxicillin
  • 1. 12 Antibacterial drug Levofloxacin
  • 1.13 Related videos:

Explore the list of 8 groups of antibacterial drugs and get detailed information about the best antibiotics that will help get rid of various infections with a high level of effectiveness and safe for health. The use of antibiotics should be carried out under the recommendation of a doctor who will determine the dosage, duration of the course and the specific drug depending on the type of infection.

Antibacterials are medicines used to treat various infectious diseases caused by bacteria. There are several groups of antibiotics, each of which is aimed at suppressing certain types of bacteria.

One of the main tasks of an infectious disease doctor is to choose the right drug for a particular patient, taking into account the type of infection, age, the presence of allergic reactions and other factors. Listed below are the 8 groups of antibacterial drugs most widely used in medicine.

1. Penicillins are the oldest group of antibiotics that were first discovered in the middle of the 20th century. They act on a wide range of bacteria and are highly effective in the treatment of many infections.
2. Cephalosporins are a group of antibiotics that act on bacteria that cause infections in the respiratory tract, urinary tract, skin and teeth. They are also widely used in surgery to prevent postoperative infections.
3. Macrolides are a group of antibiotics used to treat infections of the upper respiratory tract, skin and soft tissues. They are often prescribed for allergies to penicillins.
4. Aminoglycosides are a group of antibiotics that act on bacteria that cause severe urinary tract, lung, bone and joint infections. They are often used to treat patients in hospitals.
5. Lincosamides is a group of antibiotics used to treat infections caused by anaerobic bacteria. They can also be used as an alternative to macrolides in the treatment of respiratory or skin infections.
6. Fluoroquinolones are a group of antibiotics that act on bacteria that cause urinary tract, genital, lung and skin infections. They are often prescribed as a treatment for urogenital infections.
7. Tetracyclines are a group of antibiotics that act on bacteria that cause respiratory, urinary, and skin infections. They are also used to treat sexually transmitted infections.
8. Carbapenems are a group of antibiotics that act on bacteria that cause severe infections, including bone, lung and hospital infections. Carbapenems are used as a last line of treatment when other antibiotics do not work.

Antibacterials: groups and best examples

There are 8 groups of antibiotics, which are classified according to their mechanism of action and chemical structure. Each group has its own specific activity and is used to treat certain infections.

The second group is cephalosporins. They are more stable in acidic environments and are more widely used for more serious infections. Particularly effective are cefotaxime, ceftriaxone, and cefepime.

The third group is macrolides. These antibiotics act on the bacterium, preventing it from multiplying. These include erythromycin, clarithromycin, and azithromycin.

The fourth group is tetracyclines. They are widely used in the treatment of various infections, including respiratory and genitourinary infections. A famous example is doxycycline.

Fifth group – aminoglycosides. These antibiotics are powerful bactericidal and are used to treat severe infections such as sepsis and pneumonia. Gentamicin, tobramycin and amikacin are the most widely used.

Sixth group – lincosamides. They are also used to treat severe infections and have anti-inflammatory effects. These include lincomycin and clindamycin.

Seventh group – carbapenems. They are powerful antibiotics and are widely used to treat infections caused by many different bacteria, including those resistant to other groups of antibiotics. Of these, the best known are imipenem and meropenem.

Eighth group – fluoroquinolones. They are effective in treating a variety of infections, including acute and chronic bronchitis, bacterial diarrhea, and urinary tract infection. These include ofloxacin, levofloxacin, and ciprofloxacin.

The above groups of antibiotics are the main ones, but there are other groups of antibacterial drugs on the market.

Group of beta-lactam antibiotics

Beta-lactam antibiotics are one of the most widely used groups of antibiotics. Their basis is the beta-lactam ring fragment in their chemical structure.

Beta-lactam drugs fall into four main categories:

• Penicillins
• Cephalosporins
• Carbapenems
• Monobactams

Penicillins are widely used to treat infections caused by various bacteria, including pneumococci, streptococci, and staphylococci. Cephalosporins are also widely used to treat infections and are usually an alternative if penicillins are ineffective or cannot be used. Carbapenems are strong antibiotics often used in the hospital to treat severe infections caused by various bacteria, including Pseudomonas and Acinetobacter. Monobactams are a relatively new class of antibiotics used to treat infections caused by Gram-negative bacteria such as Pseudomonas and Haemophilus influenzae.

Some examples of beta-lactam antibiotics: Penicillin drugs Cephalosporin drugs 0282

Ceftriaxone Amoxiclav Cefepime

Group of macrolide antibiotics

Macrolide antibiotics are one of the most widely used groups antibiotics. They are used to treat various infections such as respiratory, genitourinary, gastroenterological, skin and other types of infections. The macrolide group includes drugs such as azithromycin, erythromycin, clarithromycin, and others.

The mechanism of action of macrolide antibiotics is based on the fact that they block the synthesis of proteins in the bacterial cell, which leads to its death. Also, macrolides have the properties of immunomodulators, helping to suppress inflammation and increase immunity.

The advantage of macrolides over other antibiotics is their relative safety and broad spectrum of activity. They are well tolerated by patients and usually do not cause serious side effects. However, like other antibiotics, macrolides can cause allergic reactions and intestinal dysbiosis.

• Azithromycin is considered the most effective and widely used in this group of drugs, due to its long duration of action and the fact that it can be used to treat bacterial infections of any location.
• Erythromycin is more active against gram-positive bacteria than azithromycin, but less effective against bacteria that cause urinary tract infections.
• Clarithromycin has the added benefit of better tissue and vascular penetration than other macrolides, making it more effective against respiratory tract infections.

Tetracycline antibiotic group

Tetracycline antibiotics are a group of medicines that are used to fight many types of bacteria. These antibiotics have a wide spectrum of activity and are used to treat infectious diseases such as pneumonia, urinary tract infections, skin infections, etc.

Some of the most commonly used tetracycline antibiotics include tetracycline, doxycycline, minocycline and oxytetracycline.

Like all antibiotics, tetracyclines can cause side effects and it is important to check with your doctor or pharmacist before taking these medicines. Tetracyclines are not recommended for children under 12 years of age, pregnant women and nursing mothers.

Examples of tetracycline antibiotics Available as…

Tetracycline	Tablets, capsules
Doxycycline	Tablets, capsules , syrup
Minocycline	Tablets, capsules
Oxytetracycline	Tablets, capsules

Aminoglycosis group

Aminoglycoside antibiotics are a group of bactericidal drugs that act on bacterial cells by interfering with protein synthesis. They can also produce effects on certain types of cells and tissues, but are more often used only as antibacterial drugs.

Aminoglycosides are often used to treat severe infections caused by Gram-negative bacteria. Including pathogens such as Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae.

Aminoglycosides have a number of typical representatives: gentamicin, kanamycin, amikacin, streptomycin and others. Each of them has its own characteristics, designed to defeat certain types of bacteria.

Thus, aminoglycoside antibiotics remain an important group of drugs for the treatment of severe infections caused by gram-negative bacteria. Their use requires special care and only after a careful assessment of the side effects in a particular case.

Quinolone antibiotic group

Quinolone antibiotics are a group of bactericides used to treat infectious diseases. They have a wide spectrum of activity and are well tolerated by patients.

Quinolones act on bacteria by inhibiting their ability to synthesize DNA, which leads to their death. Thus, they can be used to treat infections caused by both Gram-positive and Gram-negative bacteria.

• Examples of quinolone antibiotics:
  • Ciprofloxacin
  • Ofloxacin
  • Levofloxacin
  • Norfloxacin
  • Moxifloxacin

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  Quinolones can be used to treat infections of the respiratory tract, urinary tract, skin infections, infections of the gastrointestinal tract, as well as to prevent infections in immunocompromised states.

  Group of glycopeptides

  Glycopeptides is a group of antibiotics that are intended for the treatment of infections caused by gram-positive bacteria. Usually used to treat pathogens that cause infections of the skin, respiratory tract, bones and purulent blood infections. They are relatively new drugs that have become available for use only recently.

  Preparations of the glycopeptide group:

  • Vancomycin is one of the most commonly used representatives of the glycopeptide group. It is widely used to treat infections caused by bacteria resistant to other types of antibiotics. It is recommended to be used if other drugs have no effect.
  • Telavancin – effective against most gram-positive bacteria, including methicillin-resistant strains of staphylococci. It has a fast action and a wide spectrum of action.
  • Oritavancin – is prescribed for the treatment of skin and soft tissue infections, as well as pneumonia in patients suffering from chronic diseases. It is well tolerated and has minimal side effects.

  Contraindications and side effects:

  Preparations of the glycopeptide group have several contraindications and possible side effects. Some of them can be toxic to the kidneys and/or liver, which can lead to serious complications. Allergic reactions, nausea, vomiting, and diarrhea may also occur.

  It is necessary to consult a doctor before starting treatment with drugs of the glycopeptide group. In addition, the recommended dose and duration of treatment should not be exceeded.

  Lincosamide group

  Lincosamides are a group of antibiotics that are active against gram-positive bacteria, including staphylococci, streptococci and pneumococci. They are synthesized by microorganisms that produce them as a defense against other bacteria. Lincosamides are used to treat infections caused by these bacteria, including infections of the skin, respiratory tract, and urogenital system.

  The main member of the group is erythromycin, which has a wide spectrum of action and is often used to treat upper respiratory tract infections. Also in the group of lincosamides are clarithromycin, which has greater activity against gram-negative bacteria, as well as azithromycin, which has a long half-life and can be taken once.

  • Benefits of lincosamides:
  • broad spectrum;
  • good tolerance;
  • choice of dosage and formulation;
  • few side effects.

  Disadvantages:

  1. High price compared to some other groups of antibiotics;
  2. Development of resistance to this group of antibiotics.

  Polymyxin group

  Polymyxin is a group of antibiotics that were discovered in 1947 year. They have a broad spectrum of activity and are active against many Gram-negative bacteria such as Escherichia coli, Salmonella, Klebsiella pneumoniae, Pseudomonas aeruginosa.

  Polymyxins may be used to treat pneumonia, urinary tract infections, sepsis, skin infections, and other infections caused by Gram-negative bacteria.

  Despite their toxicity, polymyxins remain an important tool in the fight against infections caused by many Gram-negative bacteria that have become resistant to other antibiotics. They should only be used after other antibiotics have been tried and failed or cannot be used for other reasons.

  Antibacterial Azithromycin

  Azithromycin is a macrolide antibiotic used to treat a variety of infections caused by bacteria, including pneumonia, bronchitis, sinusitis, tracheitis, urinary tract infections, skin infections, and other conditions. This drug has a wide spectrum of action and is considered one of the most effective antibiotics.

  Azithromycin is available in several forms: tablets, capsules, suspension and powder for intravenous solution. The main advantage of this drug is its short course of treatment – usually it is enough to take tablets or capsules for 3-5 days. It is also generally well tolerated and has few side effects.

  It is important to remember that azithromycin is an antibiotic and should only be taken with a doctor’s prescription. Do not exceed the recommended dose and duration of the drug. If side effects occur, you should immediately consult your doctor.

  • Benefits:
  • Broad spectrum;
  • Short course of treatment;
  • Minimum number of side effects.
  1. Purpose:
  2. Treatment of infections of the respiratory tract, genitourinary system, skin infections, etc.

  Antibacterial drug Amoxicillin

  Amoxicillin is an antibacterial drug that belongs to the group of semi-synthetic penicillins. It is widely used to treat various infections caused by bacteria.

  The mechanism of action of amoxicillin is based on the fact that it destroys bacteria by inhibiting the synthesis of their cell walls. The drug is active against many types of bacteria, including staphylococci, streptococci, pneumococci, salmonella, shigella and others.

  Amoxicillin is taken orally, in one dose or divided into several doses. The dosage and duration of the course of treatment depend on the type of infection and its severity, as well as on the age and weight of the patient.

  Side effects of amoxicillin include allergic reactions, diarrhea, nausea and vomiting. In addition, the drug may interact with certain other drugs.

  • Amoxicillin is one of the most common and most effective antibacterial drugs.
  • The drug can be prescribed to adults and children, including newborns.
  • Although highly effective, amoxicillin cannot treat infections caused by viruses, fungi, and protozoa.

  If you are being treated with amoxicillin, follow your doctor’s instructions and do not stop treatment prematurely, even if the symptoms of the infection have gone. This will help prevent recurrence of the infection and reduce the risk of developing bacterial resistance.

  Antibacterial drug Levofloxacin

  Levofloxacin is a fluoroquinolone antibiotic used to treat infections caused by susceptible organisms. It penetrates into bacterial cells and disrupts their viability by blocking DNA synthesis.

  Levofloxacin is effective against a wide range of bacteria, including Gram-positive, Gram-negative, weather-resistant and anaerobic organisms.

  Levofloxacin is most commonly used to treat bacterial infections of the respiratory tract, genitourinary system, skin, soft tissues, and bones. It also has an anti-inflammatory effect, so it can be used to treat acute bronchi and exacerbations of chronic lung diseases.

  • Levofloxacin is not recommended for children under 18 years of age, pregnant or lactating women, or patients with kidney or liver problems.
  • Side effects may include diarrhea, nausea, headache, constipation and drowsiness.
  • Levofloxacin should be taken strictly according to the doctor’s prescription and the dosage should be observed.

  Levofloxacin is one of the most effective antibacterial drugs and can be used if you are allergic to other categories of antibiotics.