Diagnosis and Management of Uncomplicated Urinary Tract Infections

SUSAN A. MEHNERT-KAY, M.D.

Am Fam Physician. 2005;72(3):451-456

Patient information: See related handout on urinary tract infections, written by the author of this article.

Author disclosure: Nothing to disclose.

Most uncomplicated urinary tract infections occur in women who are sexually active, with far fewer cases occurring in older women, those who are pregnant, and in men. Although the incidence of urinary tract infection has not changed substantially over the last 10 years, the diagnostic criteria, bacterial resistance patterns, and recommended treatment have changed. Escherichia coli is the leading cause of urinary tract infections, followed by Staphylococcus saprophyticus. Trimethoprim-sulfamethoxazole has been the standard therapy for urinary tract infection; however, E. coli is becoming increasingly resistant to medications. Many experts support using ciprofloxacin as an alternative and, in some cases, as the preferred first-line agent. However, others caution that widespread use of ciprofloxacin will promote increased resistance.

Uncomplicated urinary tract infections (UTIs) are one of the most common diagnoses in the United States. In 1997, an estimated 8.3 million physician office visits were attributed to acute cystitis.¹ A U.S. and Canadian study showed that approximately one half of all women will have a UTI in their lifetimes, and one fourth will have recurrent infections.² The health care costs associated with UTIs exceed 1 billion dollars^3,4; therefore, any advance in the diagnosis and treatment of this entity could have a major economic impact. Streamlining the diagnostic process could also decrease morbidity and improve patient outcomes and satisfaction.

Clinical recommendation	Evidence rating	References
A three-day course of trimethoprim-sulfamethoxazole (TMP/SMX; Bactrim, Septra) is recommended as empiric therapy of uncomplicated urinary tract infections (UTIs) in women, in areas where the rate of resistanceEscherichia coli are less than 20 percent.	C	24
Fluoroquinolones are not recommended as first-line treatment of uncomplicated UTIs in order to preserve their effectiveness for complicated UTIs.	C	24
Use of betalactam antibiotics is not recommended for the routine treatment of uncomplicated UTIs because of limited effectiveness.	C	24
For treatment of uncomplicated urinary tract infections in older women, consider short or longer (three to 10 days) courses of antibiotics.	B	25

Epidemiology

Escherichia coli is the most common cause of uncomplicated UTI and accounts for approximately 75 to 95 percent of all infections.^2–5 A longitudinal study⁶ of 235 women with 1,018 UTIs found that E. coli was the only causative agent in 69.3 percent of cases and was a contributing agent in an additional 2.4 percent of cases. Staphylococcus saprophyticus is a distant second, accounting for only 5 to 20 percent of infections. Other Enterobacteriaceae, such as Klebsiella and Proteus, occasionally cause UTI.^2,3,5 Although S. saprophyticus is less common than E. coli, it is more aggressive. Approximately one half of patients infected with S. saprophyticus present with upper urinary tract involvement, and these patients are more likely to have recurrent infection.³

Diagnosis

Uncomplicated UTI occurs in patients who have a normal, unobstructed genitourinary tract, who have no history of recent instrumentation, and whose symptoms are confined to the lower urinary tract. Uncomplicated UTIs are most common in young, sexually active women. Patients usually present with dysuria, urinary frequency, urinary urgency, and/or suprapubic pain. Fever or costovertebral angle tenderness indicates upper urinary tract involvement. Studies show that no laboratory tests, including urinalysis and culture, can predict clinical outcomes in women 18 to 70 years of age who present with acute dysuria or urgency.⁷ Dipstick urinalysis, however, is a widely used diagnostic tool. A dipstick urinalysis positive for leukocyte esterase and/or nitrites in a midstream-void specimen reinforces the clinical diagnosis of UTI. Leukocyte esterase is specific (94 to 98 percent) and reliably sensitive (75 to 96 percent) for detecting uropathogens equivalent to 100,000 colonyforming units (CFU) per mL of urine.⁵ Nitrite tests may be negative if the causative organism is not nitrate-reducing (e.g., enterococci,S. saprophyticus, Acinetobacter). Therefore, the sensitivity of nitrite tests ranges from 35 to 85 percent, but the specificity is 95 percent.⁸ Nitrite tests can also be false negative if the urine specimen is too diluted.³ Microscopic hematuria may be present in 40 to 60 percent of patients with UTI.

Routine urine cultures are not necessary because of the predictable nature of the causative bacteria. However, urinalysis may be appropriate for patients who fail initial treatment. Current literature suggests that a colony count of 100 CFU per mL has a sensitivity of 95 percent and a specificity of 85 percent,³ but the Infectious Diseases Society of America (IDSA) recommends using a colony count of 1,000 CFU per mL (80 percent sensitivity and 90 percent specificity) for symptomatic patients. ^3,5 A cutoff of 100,000 CFU per mL defines asymptomatic bacteriuria. Physicians may have to request that sensitivities be performed on low-count bacteria if low counts are not the standard in their community.

After reviewing existing data on uncomplicated cystitis, the Group Health Cooperative of Puget Sound implemented evidence–based guidelines for treating adult women with acute dysuria or urgency.⁷ These guidelines support treating women based on symptoms alone after phone triage by a nurse. These guidelines have reduced doctor visits and laboratory tests without increasing adverse outcomes.⁷ A study⁹ of these guidelines found that women treated by telephone triage had a 95 percent satisfaction rate. The study also found that if these guidelines were used for 147,000 women ages 18 to 55 years who were enrolled in the plan, it could save an estimated $367,000 annually.⁹ A much smaller study¹⁰ comparing telephone triage with office visits for treating symptomatic cystitis showed no difference in symptom improvement scores or overall patient satisfaction.

Treatment

Many studies in the last decade have focused on the treatment length of standard therapies. A study¹¹ comparing a three-day course of ciprofloxacin (Cipro) 100 mg twice daily, ofloxacin (Floxin) 200 mg twice daily, and trimethoprim-sulfamethoxazole (TMP-SMX; Bactrim, Septra) 160/800 mg twice daily, found that all three had comparable efficacy in managing uncomplicated UTI. Another study¹² comparing a short course (three days) of ciprofloxacin (100 mg twice daily) with the more traditional seven-day course of TMP-SMX (160/800 mg twice daily), and nitrofurantoin (Furadantin) (100 mg twice daily) found that ciprofloxacin had superior bacteriologic eradication rates after short-term follow-up (four to six weeks). All three medications had similar eradication rates immediately after therapy.¹² The study¹² also found that treatment failures associated with nitrofurantoin were more common in nonwhite women older than 30 years, but researchers were unable to account for this difference.

E. coli’s resistance to TMP-SMX is an increasing problem across the United States.¹³ A recent article¹⁴ that reviewed data from The Surveillance Network (TSN) database reported thatE. coli had an overall resistance rate of 38 percent to ampicillin, 17.0 percent to TMP-SMX, 0.8 percent to nitrofurantoin, and 1.9 to 2.5 percent to fluoroquinolones. The article¹⁴ also reported thatE. coli strains resistant to TMP-SMX had a 9.5 percent rate of concurrent ciprofloxacin resistance versus a 1.9 percent rate of concurrent resistance to nitrofurantoin. Another review¹⁵ of data from TSN (January through September 2000) found that 56 percent ofE. coli isolates were susceptible to all tested drugs including ampicillin, cephalothin (Keflin), nitrofurantoin, TMP-SMX, and ciprofloxacin. Among the tested antimicrobials,E. coli had the highest resistance rate to ampicillin (39.1 percent), followed by TMP-SMX (18.6 percent), cephalothin (15. 6 percent), ciprofloxacin (3.7 percent), and nitrofurantoin (1.0 percent).¹⁵ Resistance rates varied by region of the country. Of the more than 38,000 isolates, 7.1 percent had a multidrug resistance.¹⁵ A 1999 regional analysis¹⁶ of the United States showed that resistance to TMP-SMX was highest in the Western-Southern-Central regions, with a 23.9 percent resistance rate. The Pacific and Mountain regions had a 21.8 percent resistance rate, and the South Atlantic region had a 19.7 percent resistance rate.¹⁶ Resistance rates in southern Europe, Israel, and Bangladesh reportedly have been as high as 30 to 50 percent.⁴

Fluoroquinolones have become popular treatments for patients with uncomplicated UTI because ofE. coli’s emerging resistance to other common medications. The reported resistance rate ofE. coli to ciprofloxacin is still very low at less than 3 percent.¹³ The IDSA guidelines recommend the use of fluoroquinolones (e. g., ciprofloxacin, fleroxacin [not available in the United States], norfloxacin [Noroxin], and ofloxacin) as first-line agents in communities with greater than 10 to 20 percent resistance rates to TMP-SMX.¹⁷ An economic analysis⁴ found that a three-day regimen of ciprofloxacin was more cost-effective than a three-day regimen of TMP-SMX if the resistance rate to that drug was 19.0 percent or greater.⁴ A study¹³ comparing the newest formulation of extended-release ciprofloxacin (500 mg daily for three days) with traditional ciprofloxacin (250 mg twice daily for three days) showed equivalent clinical cure rates. A 1995 study¹⁸ comparing multidose regimens of ciprofloxacin showed that the minimal effective dosage was 100 mg twice daily. Another study¹⁹ compared a single 400-mg dose of gatifloxacin (Tequin), with three-day regimens of gatif loxacin (200 mg twice daily) and ciprof loxacin (100 mg twice daily). The single-dose therapy had a clinical response rate equivalent to the two three-day regimens. Gatifloxacin is also expected to be 1,000 times less likely than older fluoroquinolones to become resistant because of its 8-methoxy structure.¹⁹

Fosfomycin (Monurol) is another treatment option for patients with UTI. The U.S. Food and Drug Administration (FDA) indicates fosfomycin for the treatment of women with uncomplicated UTI. A study²⁰ comparing a single dose of fosfomycin (3 g) with a seven-day course of nitrofurantoin (100 mg twice daily) showed similar bacteriologic cure rates (60 versus 59 percent, respectively).²⁰ Fosfomycin is bactericidal and concentrates in the urine to inhibit the growth of pathogens for 24 to 36 hours.²⁰ When fosfomycin entered the market in 1997, unpublished studies submitted to the FDA found that it was significantly less effective in eradicating bacteria than seven days of ciprofloxacin or 10 days of TMP-SMX (63 percent, 89 percent, and 87 percent eradication rates, respectively).²¹

Cephalosporins, including cephalexin (Keflex), cefuroxime (Ceftin), and cefixime (Suprax), can also manage UTIs. Increasing resistance, however, has limited their effectiveness.² The broad spectrum of this class also increases the risk of vulvovaginal candidiasis. Cephalosporins are pregnancy category B drugs, and a seven-day regimen can be considered as a second-line therapy for pregnant women.²Table 1 summarizes the possible treatments in patients with UTI.

Drug	Dosage (mg)	Frequency	Duration (days)	Cost per day*	Pregnancy category
TMP-SMX (Bactrim, Septra)	160/800†	Twice daily	Three	$3.88 (Bactrim DS)	C
				$4.00 (Septra)
Ciprofloxacin (Cipro)	250	Twice daily	Three	$10. 15 (tablet)	C
Extended-release ciprofloxacin (Cipro XR)	500	Daily	Three	$8.66	C
Nitrofurantoin (Furadantin)	100	Twice daily	Seven to 10	$17.13	B
Fosfomycin (Monurol)	3,000 (3 g)	Daily	One	$36.49	B
Cephalexin (Keflex)	250	Four times daily	Seven to 10	$6.59 (250 mg)	B
	500	Twice daily	Seven to 10	$6.47 (500 mg)
Gatifloxacin (Tequin)	400	Single dose	One	$9. 57 (400 mg)	C
	200	Twice daily	Three	$9.57 (200 mg)	C

NONPHARMACOLOGIC THERAPIES

Physicians commonly recommend nonpharmacologic options (e.g., drinking cranberry juice or water) to patients with cystitis. A Cochrane review²² found insufficient evidence to recommend the use of cranberry juice to manage UTI.

Similarly, no scientific evidence suggests that women with cystitis should increase their fluid intake, and some doctors speculate that increased fluid may be detrimental because it may decrease the urinary concentration of antimicrobial agents.¹⁷

OLDER WOMEN

Treating older women who have UTIs requires special consideration. A recent study²³ compared a 10-day course of ciprofloxacin (250 mg twice daily) with a 10-day course of TMP-SMX (160/800 mg twice daily). The study, which included 261 outpatient and institutionalized women with an average age of approximately 80 years, showed a 96 percent bacteriologic eradication rate with ciprofloxacin compared with an 80 percent eradication rate with TMP-SMX for the three most common isolates.²³ Although the IDSA did not study postmenopausal women specifically, its review found that evidence supports the use of a seven-day antibiotic regimen for older women. The three-day therapy had a higher failure rate when compared with the seven-day regimen.²⁴ A Cochrane review²⁵ found insufficient evidence to recommend for or against short- versus long-term (seven to 10 days) treatment of uncomplicated UTIs in older women.

The incidence of UTI in men ages 15 to 50 years is very low, and little evidence exists on treating them. Risk factors include homosexuality, intercourse with an infected woman, and lack of circumcision. The limited available data are similar on two key points. First, the data show that men should receive the same treatment as women with the exception of nitrofurantoin, which has poor tissue penetration.¹⁷ Second, a minimum of seven days is the recommended treatment length, because the likelihood of complicating factors is higher than in women.^5,17

Recommendations

After reviewing the available clinical data as of 1999 and classifying it by quality of evidence, the IDSA published guidelines for the use of antimicrobial agents to treat women with UTI.²⁴ The American Urological Association and the European Society of Clinical Microbiology and Infectious Diseases have endorsed these guidelines,^2,17 which can be summarized into four main recommendations. First, the IDSA recommends a three-day course of double-strength TMP-SMX as empiric therapy in areas whereE. coli resistance rates are below 20 percent. Second, although it recognizes that they have efficacy rates similar to TMP-SMX, the IDSA does not recommend fluoroquinolones as universal first-line agents because of resistance concerns. Third, the IDSA recommends a seven-day course of nitrofurantoin or a single dose of fosfomycin as reasonable treatment alternatives. Finally, the IDSA does not recommend the use of betalactams because multiple studies have shown them to be inferior when compared with other treatments.²³

Figure 1 is an algorithm for the management of uncomplicated UTIs.

Antibiotic-resistant urinary tract infections are on the rise

There is a global crisis of antibiotic resistance, and urinary tract infections (UTIs) may be the canary in the coal mine. UTIs are one of the most common types of infections; at least one in two women and one in 10 men will experience a UTI in their lifetime.

Like many human infections, UTIs are usually caused by bacteria living on or in our bodies, and require treatment with antibiotics. What’s alarming the medical community now is that UTIs are becoming ever harder to treat with common antibiotics.

Antibiotic overuse leads to antibiotic resistance

At some point, most people have taken a course of trimethoprim/sulfamethoxazole (Bactrim) or ciprofloxacin (Cipro), two common antibiotics used for UTIs. However, in the last few years it has become clear that the likelihood these antibiotics will kill most UTIs is dropping rapidly. You may have read the recent, frightening New York Times article reporting one in three uncomplicated UTIs in young healthy women are Bactrim-resistant and one in five are resistant to five other common antibiotics. Pretty scary, since we (the medical community) used to feel confident that writing a prescription for Bactrim was a sure recipe for cure.

How is it that we are losing the antibiotic war with bacteria? Though many things drive bacterial resistance, giving antibiotics to animals and antibiotic overuse in humans top the list.

We use a lot of antibiotics in humans — too much, and not always for the right reasons. When we prescribe antibiotics for viral illnesses like a cold, the flu, or common sinusitis, we create a massive shift in the body’s bacteria for no good reason (antibiotics are useless against viral infections).

Antibiotics can be lifesaving when needed. But when they aren’t needed, they kill good and bad bacteria alike, putting the body’s bacteria under intense pressure to survive. And, bacteria are real survivors! Under pressure, bacteria exchange genetic material and evolve, gaining survival traits like the ability to pump out, break down, or avoid antibiotics we want to use against them. Without antibiotic tools to kill them, these bacteria can attack us freely, and sometimes win.

Carefully targeted antibiotic treatment for urinary tract infections

So what do we do now? As a society and as individuals, we should reduce and carefully target antibiotic use. Both physicians and patients should be aware of the grave potential to lose effective antibiotics for all infections — even simple UTIs. It’s an opportunity that empowers individuals to have informed conversations with their doctors. Every time your doctor prescribes an antibiotic, ask: Do I need this? Why? Is there an antibiotic-free alternative? Talking about it might be enough to meaningfully reduce inappropriate antibiotic use.

If you’re having UTI symptoms like burning with urination, more frequent urination, bloody or cloudy urine, low abdominal pain, or fever, you should see a medical provider to get tested. You’ll have to urinate into a container and the medical office will test for products of bacterial metabolism. Make sure to tell your provider if you’ve had UTIs before, and what antibiotic you took. If you have a history of antibiotic-resistant infections, share that, too. There are alternatives to Cipro and Bactrim, but antibiotic choices are limited.

If you’re diagnosed with a UTI, your provider may prescribe an antibiotic without additional testing. Or, they might do a urine culture to test the bacteria against specific antibiotics before deciding which one to prescribe. This will become more common as antibiotic resistance increases. Antibiotic testing involves growing a sample of urine in a petri dish, finding the bacteria causing infection, and testing them against a range of antibiotics to see which ones kill the bacteria best. This process takes time and money, but it’s important to get the right treatment for your infection. While you wait for the results, taking over-the-counter analgesics like acetaminophen or ibuprofen and drinking more water can help to relieve UTI pain and discomfort.

If antibiotic resistance continues to grow, more people will need intravenous treatment for UTIs we used to cure with simple oral antibiotic courses. We’re also likely to see more complications, like kidney infections and sepsis, arising from ineffective treatment.

An ounce of prevention

Unfortunately, most UTIs are not completely preventable, and are caused by differences in the structure or function of the urinary tract and immune system. But there are things you can do to keep healthy. For example, stay hydrated to increase urine production and flush out unwanted bacterial intruders. Good hygiene is also important, but scrubbing away at delicate genital tissues can damage them and create portals for bacteria. Clean your genital area gently with mild soap and water. Postmenopausal women may benefit from vaginal estrogen cream. Finally, eating cranberries and urinating after having sex haven’t been proven to have major benefits, but aren’t likely to hurt, either.

Follow me on Twitter @lisa_xpond

instructions for use, description, reviews of patients and doctors, analogues

Some facts about the product:

Instructions for use

Presentation, composition and packaging

Bactrim is made as a liquid mixture for internal administration. The active ingredients are sulfamethoxazole and trimethoprim. Excipients:

• methylparaben;
• parahydroxybenzoic acid propyl ester;
• flavoring agent;
• fragrances;
• distilled water.

According to the description, the solution is a homogeneous suspension of yellow-white or orange color with a fruity odor.
Packing – 50- and 100-mm glass containers in a set with a measuring spoon. The price of Bactrim is regulated by the legislation of the Russian Federation.

Pharmacological action

Bactrim is an antimicrobial agent with a complex spectrum of action. Sulfamethoxazole has a bacteriostatic effect when, as a result of blocking the reactions of PABA removal, the process of formation of dihydrofolic acid in bacterial cells is suppressed. Trimethoprim inhibits the fermentation and breakdown of folic acid, transforming dihydrofolate into tetrahydrofolate. Under the influence of the agent, two successive phases of the formation of imidazo-pyrimidines and biopolymers formed by nucleotide residues, which are responsible for the creation and development of pathogens, are inhibited. A feature of the drug is the formation of a high saturation of the material in various tissues and body fluids – bone fibers, prostate, kidneys, lungs, bile and cerebrospinal secretions, saliva, lacrimal fluid, in breast lactose.
After the introduction of 90% of the initial volume of the substance is absorbed into the tissues, reaching a maximum density after 1-4 hours. It is found in breast lactose. The level of connection with plasma proteins in sulfamethoxazole is 65%, in trimethoprim – 45%.
Cleavage reactions occur with the creation of acetylated metabolites, which are not active in antimicrobial terms. They are extracted by 80% through the urinary system within three days. A small part of the drug comes out through the digestive tract. The half-life in adult patients is within 9-12 hours, in newborns – 7-8 hours, from a year to 10 years – 5-6 hours. In patients with kidney pathologies and the older age group, the elimination time increases.

Readings

Bactrim is prescribed for infectious diseases of the urinary system, respiratory system, gastrointestinal tract, ENT organs, skin, bone tissue.

Contraindications

It is forbidden to use the medication for liver parenchyma disease, acute kidney pathologies, in case of severe forms of blood damage, high bilirubin levels. Caution is required for concomitant diseases of the thyroid organ, bronchial asthma. You can buy Bactrim at a pharmacy or in an online store.

Dosage and Administration

Bactrim is prescribed at a dose of 0.4 to 2 g 2 times a day. The portion for small children under 2 years old is set individually. The maximum daily dose cannot exceed 3.6 g. It is allowed to switch to Bactrim analogues only on the recommendation of a doctor.

Side effects

Most often, accidental phenomena against the background of the use of a combined antimicrobial chemical agent occur on the skin and in the digestive tract. There are complications from:

• blood formation and lymphatic system – decrease in the level of leukocytes, granulocytes, platelets, erythrocytes;
• immunity – nettle fever, angioedema, polyarteritis nodosa, infectious-allergic myocarditis, dermatitis, lupus erythematosus;
• metabolism – an increase in the amount of potassium in the blood serum, a decrease in the level of sodium, sugar;
• mentality – hallucinogenic and depressive states, lack of sleep, high fatigue, psychosis, clouding of consciousness, impaired attention, perception, thinking and emotions.

The appearance of complications after the use of Bactrim is possible from:

• central nervous organization – sensory disturbance, neuritis, meningitis-like conditions, convulsions, dizziness, cephalalgia, ringing in the ears;
• respiratory system – pneumonia;
• digestive department – nausea with or without vomiting, diarrhea, inflammation of the intestines, pancreas;
• hepatobiliary structure – activation of enzymes, increased levels of bilirubin, hepatitis, necrosis of hepatocytes, symptoms of the disappearance of the bile ducts;
• renal and urinary systems – kidney dysfunction, tubulointerstitial chronic nephritis, increased levels of urea, creatinine in the blood, the formation of salts in the urine, increased diuresis;
• skin – the appearance of a rash.

In HIV-infected patients during treatment with the introduction of high doses of Bactrim, according to doctors, pneumonia develops. In 20-25% of patients, the drug has to be discontinued due to severe side effects from:

• psychics – acute psychoses;
• nervous organization – hallucinations, aseptic meningitis, convulsive convulsions, trembling of the limbs like Parkinson’s syndrome, impaired motor skills, vestibular apparatus;
• digestive tract – lack of appetite, irritation of the pituitary surface of the oral cavity, neck, chin.

Many drugs containing sulfonamides cause collateral changes in the form of target-like rashes on the pituitary surface, photophobia. As a result of the use of Bactrim in the area of ​​the musculoskeletal structure, pain occurs in muscles, joints, up to destruction and necrosis of muscle tissue.

Overdose

With a strong overdose, nausea with vomiting, diarrhea, cephalgia, dizziness, impaired visual perception and cognitive abilities develop. Severe types of poisoning are characterized by the formation of salts in the urine, the appearance of blood and the impossibility of urination. Long-term use of chemical means suppresses the processes of blood formation, which causes a decrease in the level of platelets, leukocytes against the background of folic acid deficiency.
To prevent the absorption of the substance into the blood, forced diuresis is prescribed by alkalinizing the urine. Extrarenal blood purification is ineffective. The level of electrolytes and the state of the blood are monitored. In the event of the development of severe clinical changes in the blood or the onset of symptoms of jaundice, special therapy is prescribed. To reduce the effects of trimethoprim, calcium folinate is given in an amount of 3 to 6 mg per day. The duration of the course is one week. You can order Bactrim on a specialized pharmacy website.

Drug interactions

With the complex use of an antimicrobial syrup with anticoagulants of indirect influence, the effect of anticoagulants is significantly enhanced. Parallel administration with sulfonylurea metabolites causes an even sharper decrease in the sugar-lowering effect.
The combination of Bactrim with methotrexate enhances the toxic effect of the latter and leads to the development of pancytopenia due to a break in its connection with blood plasma proteins.
Under the influence of anti-inflammatory drugs in combination with Bactrim, the effect of both substances is summed up with the occurrence of side effects. With parallel administration with diuretic materials, the likelihood of a decrease in platelet levels increases. This effect is especially characteristic for older patients.
Simultaneous administration with chloridine increases the effect of the antimicrobial agent due to the inhibition of tetrahydroflic acid, which is involved in the formation of nucleic acids and proteins. At the same time, sulfonamides slow down the synthesis of dihydrofolic acid, which precedes the appearance of tetrahydrofolic acid compounds. This combination is used to eliminate parasitic diseases.
The absorption of the active components of Bactrim when combined with cholestyramine is reduced due to a decrease in the density in the blood substance and the synthesis of insoluble compounds.
The complex use of an antimicrobial chemical agent and antiepileptic substances increases the half-life of phenytoin with a simultaneous increase in its effect and toxicity.
The combination with antimalarial chemicals increases the risk of malignant anemia. Sulfamethoxazole and trimethoprim in combination with digoxin increase the concentration of cardiotonic. In aged patients, control over the level of antiarrhythmic substance in the blood serum should be strengthened. An antimicrobial agent reduces the effectiveness of antipsychotic therapy. When combined with cyclosporine after kidney transplantation, dysfunction of the organs of the urinary structure is observed, which is expressed by an increase in the amount of creatinine in the blood medium.
Parallel administration of Bactrim with angiotensin-converting enzyme blockers has been noted to increase the level of potassium in the blood. This is especially true for older patients.
Trimethoprim, blocking the patency of the urinary system, increases the total and maximum density of dofetilide by 103% and 93% respectively. As a result, there is an inconsistency in the processes of depolarization and repolarization of the ventricular myocardium, the occurrence of ventricular arrhythmia. Bactrim delivery in Moscow is carried out around the clock.

Special instructions

Patients in childhood are prescribed only preparations containing sulfamethoxazole with trimethoprim, which are intended for use in pediatric practice. Monitoring of the level of saturation of sulfamethoxazole in blood plasma is performed every 2-3 days before the next use. When the saturation of the active ingredient in the amount of 150 mcg / ml, therapy is stopped until the indicator drops below 120 mcg / ml.
With prolonged treatment for more than 30 days, blood tests are taken due to the risk of formation of changes in it. They are reversible with daily intake of folic acid at a dose of 3-6 mg. This does not cause violations of the antimicrobial efficacy of the drug. In the presence of an initial folate deficiency in elderly patients, the appointment of an antimicrobial agent should be performed with caution.
To prevent the formation of salts in the urine, it is necessary to maintain sufficient urination. The use of Bactrim increases the risk of allergenic or toxic side effects with reduced filtration activity of the kidneys.
During therapy, it is not recommended to eat food containing PABA – green cabbage, spinach, as well as legumes, carrots, tomatoes. It is necessary to be as little as possible under the influence of sunlight, avoid visiting solariums. The likelihood of developing accidental phenomena against the background of the use of antimicrobial syrup is higher in patients with AIDS. It is not advisable to use a chemical remedy for inflammation of the larynx, which is caused by streptococcus A due to the resistance of the microorganism to the drug.
The introduction of Bactrim during the period of gestation, lactation is not shown. In renal pathology, the dosage level is determined on the basis of the creatinine clearance.

Terms and conditions of storage

According to the instructions, the shelf life of the material is 5 years when stored at t ° up to 30 ° C.

Prices for Bactrim in Moscow

Pick up the order at the pharmacy
WER (Moscow)

Favorable prices

Certificates and licenses

References

1. State Register
   medicinal
   funds
2. International Classification of Diseases, 10th Revision (ICD-10)
3. Vidal Drug Formulary

What is Bactrim used for?

Bactrim

Quick Navigation

1. What is Bactrim?
   1. Definition
   2. Components Bactrim side effects
   3. Bactrim
   4. Conclusion

   What is Bactrim?

   1.

   

   definition Rome (TMP). It has good antibacterial effects against enterobacteria such as Helicobacter, Klebsiella, Salmonella, Proteus, Morganella, Shigella, Neisseria meningitidis and Haemophilus influenzae. In particular, its antibacterial action against Escherichia coli, Haemophilus influenzae and Staphylococcus aureus is significantly stronger than that of SMZ.

   If you eat dairy products , Balla can also sulfanilamide test to tell you if there are sulfanilamide residues in them.

   sulfamethoxazole

   2.

   Ingredients

   This product is a compound preparation, each containing 0.4 g of the active ingredients sulfamethoxazole and 0.08 g of trimethoprim.

   A. Sulfamethoxazole

   a. Definition

   Sulfamethoxazole – white crystalline powder; odorless with a bitter taste. Practically insoluble in water; soluble in dilute hydrochloric acid, sodium hydroxide test solution or ammonia test solution. It is mainly used for urinary tract infections, respiratory infections, intestinal infections, biliary tract infections, and local infections of soft tissues or wounds caused by susceptible bacteria.

   On October 27, 2017, the list of carcinogens published by the International Agency for Research on Cancer of the World Health Organization was originally compiled for reference. Sulfamethoxazole has been included in the list of three types of carcinogens.

   Sulfamethoxazole is a broad-spectrum antibacterial drug that is particularly effective against Staphylococcus aureus and E. coli. It is used to treat urinary tract infections and avian cholera. Sulfamethoxazole moderately effective sulfate preparation for systemic use. It can compete with PABA for its action on dihydrofolate synthase in bacteria, preventing the synthesis of bacterial dihydrofolate, thereby inhibiting bacterial growth and reproduction. Three sulfa drugs, sulfadiazine, sulfisoxazole and trisulfadiazine, are currently the best drugs for the treatment of nocardiac diseases.

   With a half-life of 10-12 hours, it can be partially acetylated. Although the amount of medication needed for this product is less than that of sulfisoxazole (2 times a day instead of 4 times), its acetylated metabolites have lower urinary solubility, so the chance of crystalluria is slightly higher. Thus, patients should maintain adequate hydration (daily urine output in adults is at least 1,500 ml). When used together with the synergist trimethoprim, the antibacterial effect is significantly enhanced.

   Bactrim (sulfamethoxazole/trimethoprim SMZ/TMP) is often better than monotherapy (see dihydrofolate reductase). It is often used in clinical settings for the treatment of urinary tract infections, respiratory tract infections, typhoid fever, salmonella infection, pneumocystis disease, nocardiosis, etc., and also for the prevention of epidemic meningitis. Some physicians recommend a combination of minocycline, ampicillin, or erythromycin and sulfamethoxazole to treat these infections, but there is no clinical evidence to prove that the combination is better than sulfa drugs alone. Bactrim (TMP/SMZ), minocycline (minocycline; minocin), and amikacin (amikacin) may also be used to treat Nocardia stellaria infection.

   b. Contraindications

   • People who are allergic to sulfa drugs prohibited
   • Because this product prevents the metabolism of folic acid and aggravates folic acid deficiency in patients with megaloblastic anemia, this product is prohibited for patients with this disease.
   • Pregnant and lactating women should not use this product.
   • Children under 2 months of age should not use this product.
   • People with severe liver and kidney damage should not use this product.

   B. T rimethoprim

   a. Definition

   Trimethoprim , TMP for short, is a white or off-white crystalline powder; odorless, bitter taste. This product is slightly soluble in chloroform, slightly soluble in ethanol or acetone, and almost insoluble in water; easily soluble in glacial acetic acid. The melting point of this product is 199203℃, molecular formula: C14h28N4O3, molecular weight: 290.31800, absorption coefficient 198～210. Trimethoprim is a synthetic broad-spectrum antibacterial agent used alone for respiratory tract infections, urinary tract infections, intestinal infections and other diseases. It can be used to treat sepsis, meningitis, otitis media, typhoid and shigellosis caused by susceptible bacteria (bacillar dysentery), etc. The combination of trimethoprim and sulfa-2,6-dimethoxin can also be used to treat chloroquine-resistant malaria.

   b. Pharmacological effects

   Trimethoprim is an inhibitor of bacterial dihydrofolate reductase and a synergist of sulfonamides. The principle of its antibacterial action is to interfere with the metabolism of folic acid bacteria. The main goal is to selectively inhibit the activity of bacterial dihydrofolate reductase so that dihydrofolate cannot be reduced to tetrahydrofolate, thereby inhibiting the growth and reproduction of bacteria.

   Trimethoprim has antibacterial activity against most Gram-positive and Gram-negative bacteria; In addition, trimethoprim also has some effect on malaria parasites and some fungi such as Nocardia, histoplasma and yeast. Among Gram-positive bacteria, Streptococcus pneumoniae is susceptible to trimethoprim. Among gram-negative bacteria, Escherichia coli , Salmonella , Proteus mirabilis, Bacillus pneumoniae, Bacillus dysentery, Bacillus typhi, Bacillus pertussis, etc. are sensitive to trimethoprim. Trimethoprim has no antibacterial effect on Pseudomonas aeruginosa, meningococcus and alkaligens.

   c. Contraindication

   • Trimethoprim should not be used in premature or newborn infants.
   • People with liver disease, kidney disease, megaloblastic anemia due to folic acid deficiency or other disorders of the blood system should use this medicine with caution.
   • Effects of drugs on breastfeeding: trimethoprim may be excreted in breast milk in high concentrations, and the drug may affect the metabolism of folic acid in infants. Therefore, mothers should weigh the pros and cons before making a decision to take the drug.
   • Peripheral blood should be checked regularly while taking medication.

   3.

   Bactrim uses

   Because many common clinical pathogens are often resistant to this product, treatment of bacterial infections should be based on drug susceptibility results. The main indications for the use of this product are the following infections caused by susceptible strains.

   1. Urinary tract infections caused by susceptible strains of Escherichia coli, Klebsiella, Enterobacter, Proteus mirabilis, Proteus vulgaris and Morgenella.
   2. Acute otitis media in children over 2 years of age due to Streptococcus pneumoniae or Haemophilus influenzae.
   3. Acute attack of chronic bronchitis in adults caused by Streptococcus pneumoniae or Haemophilus influenzae.
   4. Intestinal and Shigella infections due to susceptible strains of Shigella flexneri or Shigella sungii.
   5. Treatment of Pneumocystis carinii pneumonia.
   6. It may prevent Pneumocystis carinii pneumonia in patients with at least one episode of Pneumocystis carinii disease or in adults with HIV infection who have a CD4 count of ≤200/mm3 or less than 20% of the total lymphocyte count.
   7. Tourist diarrhea due to enterotoxigenic Escherichia coli (ETEC).

   Bactrim side effects

   1. Allergic reactions to Bactrim are more common, which may manifest as drug rashes. In severe cases, erythema multiforme exudative, exfoliative dermatitis, and atrophic dermatitis may develop with epidermolysis bullosa; it may also manifest as photosensitivity, drug fever, joint and muscle pain, fever and other reactions similar to serum sickness, and sometimes anaphylactic shock.
   2. Neutropenia or insufficiency, thrombocytopenia and aplastic anemia. Patients may have a sore throat, fever, pallor, and a tendency to bleed.
   3. Hemolytic anemia and hemoglobinuria. They often occur after the use of sulfa drugs in patients with glucose-6-phosphate dehydrogenase deficiency, and this is more common in neonates and children than in adults.
   4. Hyperbilirubinemia and kernicterus of newborns. Because this product competes with bilirubin for protein binding sites, it may increase free bilirubin. Newborns with imperfect liver function and poor bilirubin treatment are prone to hyperbilirubinemia and neonatal jaundice, and kernicterus may occasionally occur.
   5. Liver damage. Jaundice, decreased liver function may occur, and in severe cases acute liver necrosis may occur.
   6. Kidney damage. Crystalluria, hematuria, and tubular urine may occur; Occasionally, patients may experience serious adverse reactions such as interstitial nephritis or renal tubular necrosis.
   7. Nausea, vomiting, loss of appetite, diarrhoea, headache, fatigue, etc. General symptoms are mild. Occasionally, patients develop C. difficile enteritis at which time the drug should be discontinued.
   8. Sometimes there is an increase in goiter and hypofunction.
   9. Sometimes toxic reactions from the central nervous system can occur, manifesting as confusion, disorientation, hallucinations, euphoria or depression.
   10. Occasionally, aseptic meningitis with headache, neck stiffness, nausea, etc. may develop. dermatitis, epidermolysis bullosa, atrophic dermatitis, fulminant hepatic necrosis, agranulocytosis, and abnormalities in the blood system such as insufficiency and aplastic anemia. The above adverse reactions are more common in AIDS patients than in non-AIDS patients.

   Bactrim

   People taking this medicine are prone to crystalluria, hematuria, proteinuria, oliguria, back pain, etc. Patients with liver failure should not take. bactrim tablets.

   1. Because bacteria are not easy to remove, this product should not be used as a treatment or prophylactic for the following conditions:
      • Prophylaxis or long-term treatment of otitis media.
      • Group A hemolytic streptococcal tonsils and pharyngitis.
   2. Cross-reactivity. Patients allergic to one sulfate preparation may also be allergic to other sulfa preparations.
   3. Liver injury. Jaundice, decreased liver function may occur, and in severe cases, acute liver necrosis may occur, so patients with liver damage should avoid use.
   4. Kidney damage. Crystalluria, hematuria and tubular urine can occur easily, so you should drink more water while taking the product to maintain a high urine flow. If the product is used for a long course of treatment and high doses, in addition to drinking more water, it is recommended to take sodium bicarbonate together to prevent this side reaction.
   5. Use of this product in patients with dehydration or shock may cause kidney damage and should therefore be used with caution or avoided. Patients with impaired renal function should not use this product.
   6. Patients allergic to furosemide, sulfones, thiazide diuretics, sulfonylureas, and carbonic anhydrase inhibitors may also be allergic to sulfanilamide preparations .
   7. The following conditions should be used with caution: patients with glucose-6-phosphate dehydrogenase deficiency, hematoporphyrias, blood system diseases with folic acid deficiency, dehydration, AIDS or shock.
   8. Severely infected patients should measure the drug concentration in the blood, which is effective for most infected patients with a free sulfonamide concentration of 50–150 g/ml (for severe infections, 120–150 µg/ml). The total concentration of sulfur in the blood should not exceed 200 g / ml, otherwise the frequency of adverse reactions will increase.
   9. Do not arbitrarily increase the dose, increase the frequency of medication or prolong the course of treatment to prevent accumulated poisoning.
   10. Since this product may inhibit the growth of E. coli and interfere with the synthesis of B vitamins in the intestines, people who use this product for more than a week should also be given vitamin B to prevent vitamin B deficiency. product, you can take folic acid preparations at the same time, the latter does not affect the antibacterial activity of TMP, because bacteria cannot use the synthesized folic acid.