Prevacid ac. Prevacid: Uses, Side Effects, and Risks of This Popular Acid Reflux Medication
What is Prevacid used for. How does Prevacid work. What are the serious side effects of Prevacid. Why are there lawsuits against Prevacid. How should Prevacid be taken. What are the differences between Prevacid and Zantac. What warnings has the FDA issued about Prevacid.
What is Prevacid and How Does It Work?
Prevacid (lansoprazole) is a proton pump inhibitor (PPI) medication used to treat conditions related to excess stomach acid. It works by decreasing the amount of acid produced in the stomach, allowing time for the stomach and esophagus to heal from damage caused by acid reflux.
Specifically, Prevacid blocks an enzyme in the stomach wall responsible for releasing acid. By reducing stomach acid, it can prevent ulcers from developing or recurring and alleviate symptoms of acid reflux and related conditions.
FDA-Approved Uses for Prevacid
- Treating and maintaining duodenal ulcers
- Certain gastric ulcer treatments
- Treating symptoms of gastroesophageal reflux disease (GERD)
- Treatment and maintenance of erosive esophagitis (EE)
- Treating Zollinger-Ellison syndrome and other hypersecretory conditions
- H. pylori treatment
It’s important to note that Prevacid is not intended for immediate heartburn relief. It typically takes up to four days to effectively relieve symptoms. Additionally, lansoprazole, the active ingredient in Prevacid, is not effective at treating symptomatic GERD in infants.

Prevacid vs. Zantac: Understanding the Differences
While both Prevacid and Zantac are medications used to reduce stomach acid, they belong to different drug classes and work in distinct ways.
Key Differences Between Prevacid and Zantac:
- Prevacid is a proton pump inhibitor (PPI), while Zantac is an H2 blocker
- Prevacid affects proton pumps that generate acid through a chemical process
- Zantac prevents acid-producing cells from responding to histamines in the stomach
- Zantac was advertised to work in as little as 30 minutes, while Prevacid can take days and multiple doses to take effect
- Zantac was withdrawn from the U.S. market in 2020 due to safety concerns
Available H2 blockers that are alternatives to Zantac include famotidine (Pepcid) and cimetidine (Tagamet).
Serious Side Effects and Risks Associated with Prevacid
While short-term use of Prevacid typically doesn’t cause side effects, long-term use has been linked to several serious health risks. Studies conducted between 2000 and 2021 have associated Prevacid with potentially life-threatening complications, especially when taken for extended periods.

Serious Side Effects of Prevacid:
- Kidney damage and failure
- Increased risk of certain cancers
- Clostridium difficile-associated diarrhea
- Low magnesium levels
- Lupus erythematosus (autoimmune disease)
- Osteoporosis and fractures of the hip, wrist, and spine
- Vitamin B12 deficiency
Are there warning signs of serious Prevacid side effects? Yes, patients should be aware of symptoms that may indicate severe reactions to the medication. These include:
- Abnormal heartbeat
- Decreased or bloody urine
- Jerking muscle movements
- Muscle aches or weakness
- Seizures
- Watery or bloody diarrhea
If you experience any of these symptoms, it’s crucial to contact your doctor immediately.
FDA Warnings and Safety Concerns Regarding Prevacid
Since 2010, the U.S. Food and Drug Administration (FDA) has issued several warnings about Prevacid and other proton pump inhibitors. These warnings highlight potential risks associated with long-term use of the medication.
FDA Warnings for Prevacid Include:
- Risk of Clostridium difficile-associated diarrhea (severe diarrhea that can contain blood or pus)
- Potential for kidney disease and kidney failure due to acute interstitial nephritis (AIN)
- Increased risk of low magnesium levels
- Possible development of lupus erythematosus (an autoimmune disease)
- Higher risk of osteoporosis and fractures of the hip, wrist, and spine
- Potential for vitamin B12 deficiency
These warnings underscore the importance of using Prevacid only as directed and for the shortest duration necessary to achieve the desired therapeutic effect. Patients should discuss the risks and benefits of long-term PPI use with their healthcare providers.

Prevacid Lawsuits: Understanding the Legal Landscape
The serious side effects associated with Prevacid have led to numerous lawsuits against the manufacturer. As of July 2019, there were 12,775 pending lawsuits involving several different proton pump inhibitors, including Prevacid.
What are the main allegations in Prevacid lawsuits?
The primary claims in these lawsuits revolve around kidney-related injuries, including:
- Acute interstitial nephritis (AIN)
- Kidney disease
- Kidney failure
- Kidney injury
These lawsuits allege that the manufacturers failed to adequately warn patients and healthcare providers about the potential risks associated with long-term use of Prevacid and other PPIs.
Legal Proceedings for Prevacid Lawsuits
To streamline the legal process, a federal panel has combined the lawsuits into a multidistrict litigation (MDL) in New Jersey federal court. This consolidation allows for more efficient handling of similar cases while still preserving individual claims.
Patients who have suffered kidney problems or other serious side effects after taking Prevacid may be eligible to file a lawsuit. It’s advisable to consult with a qualified attorney to understand the legal options available.

Proper Usage and Administration of Prevacid
Prevacid is an oral medication available in various forms, including delayed-release capsules, orally disintegrating tablets, and oral suspension. The appropriate dosage and duration of treatment depend on the specific condition being treated and individual patient factors.
General Guidelines for Taking Prevacid:
- Take Prevacid exactly as prescribed by your healthcare provider
- Swallow delayed-release capsules whole; do not crush, chew, or open them
- For orally disintegrating tablets, allow the tablet to dissolve on your tongue and swallow with or without water
- Take Prevacid before meals for optimal effectiveness
- If using the oral suspension, shake well before use and use the provided dosing syringe
- Do not exceed the recommended dosage or duration of treatment without consulting your doctor
Can Prevacid be taken long-term? While Prevacid is generally intended for short-term use (10 days to 12 weeks), some patients may require longer-term treatment under medical supervision. However, given the potential risks associated with long-term use, it’s crucial to regularly reassess the need for continued therapy with your healthcare provider.

Alternatives to Prevacid: Exploring Other Treatment Options
For patients concerned about the potential risks of Prevacid or those seeking alternative treatments for acid-related conditions, several options are available. These alternatives range from other medications to lifestyle modifications.
Medication Alternatives to Prevacid:
- Other proton pump inhibitors (e.g., Nexium, Prilosec)
- H2 blockers (e.g., Pepcid, Tagamet)
- Antacids for quick, short-term relief
- Alginate-based formulations (e.g., Gaviscon)
Non-Medication Approaches:
- Dietary changes (avoiding trigger foods, eating smaller meals)
- Weight loss if overweight or obese
- Elevating the head of the bed for nighttime reflux
- Quitting smoking
- Reducing alcohol consumption
- Stress management techniques
What factors should be considered when choosing an alternative to Prevacid? The choice of treatment should be based on the specific condition, severity of symptoms, individual patient characteristics, and potential risks and benefits of each option. It’s essential to work closely with a healthcare provider to determine the most appropriate treatment plan.

The Future of Acid Reflux Treatment: Emerging Therapies and Research
As concerns about the long-term use of proton pump inhibitors like Prevacid continue to grow, researchers are exploring new approaches to treating acid reflux and related conditions. These emerging therapies aim to provide effective relief while minimizing potential side effects.
Promising Areas of Research in Acid Reflux Treatment:
- Potassium-competitive acid blockers (P-CABs): A new class of acid suppressants with potentially faster onset and longer duration of action
- Transient lower esophageal sphincter relaxation (TLESR) inhibitors: Medications that target the underlying mechanism of reflux
- Mucosal protectants: Substances that form a protective barrier on the esophageal lining
- Endoscopic therapies: Minimally invasive procedures to strengthen the lower esophageal sphincter
- Personalized medicine approaches: Tailoring treatments based on individual patient characteristics and genetic factors
How might these new therapies impact the treatment landscape for acid reflux? As research progresses, these innovative approaches could potentially offer more targeted and safer alternatives to current treatments like Prevacid. However, extensive clinical trials and long-term safety data will be necessary before these therapies become widely available.

In conclusion, while Prevacid remains an effective treatment option for many patients with acid-related conditions, it’s crucial to be aware of the potential risks associated with long-term use. Patients should work closely with their healthcare providers to weigh the benefits and risks of Prevacid and explore alternative treatment options when appropriate. As research in this field continues to advance, we can look forward to more targeted and potentially safer therapies for managing acid reflux and related disorders.
Prevacid – Uses, Side Effects, Warnings and Interactions
Prevacid (lansoprazole) is a proton pump inhibitor (PPI). Doctors may recommend it for short-term treatment of ulcers and acid reflux. Studies have linked long-term Prevacid use with several serious side effects. Prevacid users have filed lawsuits over complications from the drug.
Prevacid (lansoprazole) belongs to a class of drugs called proton pump inhibitors (PPIs). These are powerful heartburn drugs. Other PPIs include Nexium, Prilosec and Protonix.
The U.S. Food and Drug Administration approved Prevacid in 1995. Prevacid is available in prescription and over-the-counter (OTC) versions.
Between 2000 and 2021, several studies linked Prevacid to several serious health risks, especially when taken long-term. Some of the risks associated with Prevacid can result in serious injury or death. These include kidney damage and cancer. Patients have filed Prevacid lawsuits after suffering severe side effects.
People should speak with their doctors before starting or stopping Prevacid.
What Does Prevacid Treat?
Prevacid treats certain problems related to excess stomach acid. It is generally intended for short-term use — anywhere from 10 days to 12 weeks. But patients sometimes use it for longer periods of time.
Ulcers are open sores in the lining of the stomach.
FDA-Approved Prevacid Uses
- Treating and maintaining duodenal ulcers
- Certain gastric ulcer treatments
- Treating symptoms of gastroesophageal reflux disease (GERD)
- Treatment and maintenance of erosive esophagitis (EE)
- Treating Zollenger-Ellison syndrome and other hypersecretory conditions
- H. pylori treatment
Prevacid is not meant for quick relief of heartburn. It takes up to four days to relieve symptoms.
Lansoprazole is the active ingredient in Prevacid. It is not effective at treating symptomatic GERD in infants.
How Prevacid Works
Prevacid decreases the amount of acid in the stomach. It blocks an enzyme in the stomach wall from releasing acid. Decreased stomach acid gives the stomach and esophagus time to heal. It also prevents further damage and complications. This can prevent ulcers from developing or recurring.
Prevacid vs. Zantac
Prevacid is a PPI, like Nexium and Prilosec. PPIs differ from h3 blockers like Zantac and Pepcid. Both types of medication prevent the stomach from producing too much acid. But they do it in different ways.
Prevacid affects tiny proton pumps that generate acid through a chemical process. Zantac prevents acid-producing cells from responding to histamines in the stomach.
Zantac is advertised to work in as little as 30 minutes. Prevacid can take days and multiple doses to take effect. Zantac was withdrawn from the U.S. market in 2020 and is no longer available. Available h3 blockers include famotidine (Pepcid), and cimetidine (Tagamet).
Serious Prevacid Side Effects, Risks and Warnings
Studies have linked Prevacid and other PPIs to several serious side effects. PPI side effects are most common with long-term use lasting a year or more.
Short-term Prevacid use does not usually cause side effects. When side effects do occur, they are typically mild. Some of the common side effects of Prevacid are constipation, diarrhea, stomach pain and nausea.
Call your doctor right away if you experience any of the following symptoms. They could indicate serious side effects of Prevacid.
- Abnormal heartbeat
- Decreased or bloody urine
- Jerking muscle movements
- Muscle aches or weakness
- Seizures
- Watery or bloody diarrhea
The FDA has issued several Prevacid warnings since 2010.
Prevacid warnings include:
- Clostridium difficile-associated diarrhea (severe diarrhea that can contain blood or pus)
- Kidney disease and kidney failure due to acute interstitial nephritis (AIN)
- Low magnesium levels
- Lupus erythematosus (autoimmune disease)
- Osteoporosis and fractures of the hip, wrist and spine
- Vitamin B12 deficiency
For a complete list of potential side effects, symptoms and FDA warnings, speak to your pharmacist or doctor and review the drug label.
Prevacid Lawsuits
People who suffered kidney problems have filed Prevacid lawsuits. As of July 2019, there were 12,775 pending lawsuits over several different PPIs.
A federal panel combined the lawsuits in a multidistrict litigation. MDLs allow several similar lawsuits to move more quickly through the legal process. The cases are in New Jersey federal court.
Injuries Claimed in Prevacid Lawsuits
- Acute interstitial nephritis (AIN)
-
Kidney disease -
Kidney failure -
Kidney injury
Lawsuit Information
Multiple lawsuits claim Prevacid and other proton pump inhibitors caused serious side effects that led to kidney disease and failure. Read more about currently pending litigation.
View Lawsuits
How to Take Prevacid
People take Prevacid orally. It is available in delayed-release capsules and delayed-release orally disintegrating tablets.
Patients can swallow the delayed-release capsules whole. People place the disintegrating tablets on the tongue and allow them to dissolve with or without water.
Patients should take either version before a meal. People should not crush either form of the medicine.
Forms Prevacid Comes In
Prevacid comes in several forms. Over-the-counter and generic prescription versions are available. There are also store brand equivalents. All forms contain the same active ingredient, lansoprazole.
Available Prevacid Versions and Equivalents
- Prevacid
- Prescription brand-name for lansoprazole; available in capsule form
- Prevacid SoluTab
- Prescription version of Prevacid designed to dissolve; available for suspension in liquids and as a tablet that dissolves in the mouth
- Prevacid 24HR
- Over-the-counter (OTC) version of Prevacid
- Generic lansoprazole
- Generic prescription versions
- Store brands
- Includes Heartburn Relief 24 Hour and Heartburn Treatment 24 Hour; comparable to Prevacid 24HR
Prevacid Dosages
Prescription Prevacid versions come in both 15 mg and 30 mg pills.
Prevacid 24 HR comes in 15 mg pills.
Dosages can vary based on the condition Prevacid treats. Doctors may also consider the age and weight of the patient. Doctors may adjust the dosage depending on the patient’s other health conditions.
The recommended daily dosage of Prevacid in people with liver disease is 15 mg.
Recommended Prevacid Doses for Adults
| Condition Being Treated | Recommended Dose | Taken How Often & How Long |
|---|---|---|
| Duodenal ulcers | 15 mg | Once daily for 8 weeks for short-term treatment Once daily for maintenance of healed ulcer |
Eradication of H. pylori bacteria – Triple therapy | 30 mg (Prevacid)
1 gram (Amoxicillin) 500 mg (Clarithromycin) | Twice daily for 10 to 14 days |
| Benign gastric ulcer | 30 mg | Once daily for up to 8 weeks for short-term treatment |
| NSAID-associated gastric ulcer | 30 mg or 15 mg | Once daily for 8 weeks for healing
Once daily for up to 12 weeks for risk reduction |
| GERD (gastroesophageal reflux disease) | 15 mg or 30 mg | Once a day for up to 8 weeks for short-term treatment of symptomatic GERD
Once a day for up to 8 weeks for short-term treatment of erosive esophagitis (EE) |
| Maintenance of healing of erosive esophagitis (EE) | 15 mg | Once a day (controlled studies did not go beyond 12 weeks of treatment) |
| Zollinger-Ellison Syndrome | 60 mg | Once daily (doses and length of time of treatment can vary per patient) |
Recommended Prevacid Doses for Children
| Condition Being Treated | Recommended Dose | Taken How Often & How Long |
|---|---|---|
| Short-term treatment of symptomatic GERD and erosive esophagitis (EE) (ages 1 to 11) | 15 mg for kids weighing under 30 kg
30 mg for those weighing more than 30 kg 15 mg for kids weighing under 30 kg
| Once a day for up to 12 weeks |
| Short-term treatment of symptomatic GERD (ages 12 to 17) | 15 mg (non-erosive GERD) 30 mg (erosive esophagitis) | Once daily for up to 8 weeks |
Source:
U.
S. Food and Drug Administration
Several recent studies have associated side effects with PPI use in infants. A 2017 study found Prevacid given before a child’s first birthday increased bone fracture risks. And a 2018 study found PPIs taken in infancy can lead to childhood allergies.
Prevacid Overdose and Missed Dose Information
It may be possible to overdose on Prevacid. But a case study found a person who took 20 times the adult dose suffered no adverse reactions.
Tests on rats and mice found no relative overdose risk at 1,300 times the adult dose. Overdose symptoms may include passing out or trouble breathing.
“If over-exposure occurs, call your poison control center at 1-800-222-1222 for current information on the management of poisoning or over-exposure. ”
If a person misses a Prevacid dose, he or she should take a dose as soon as possible. If the person is nearing the time for the next dose, he or she may wait until the next scheduled time.
Prescription vs. Prevacid 24HR (OTC)
Prevacid is available by prescription or over-the-counter (OTC). Prevacid 24HR is the nonprescription version. Studies have found that Prevacid 24HR often works as well as prescription Prevacid. Prevacid 24HR is only available in a 15 mg dose.
People can take one Prevacid 24HR 15 mg pill daily for 14 days. Prevacid 24HR users should not take the drug for more than 14 days. They should wait at least four months before taking Prevacid 24HR again.
Who Should Not Take Prevacid?
People who are allergic to lansoprazole should not take Prevacid. People allergic to any other PPI or other Prevacid ingredient should avoid it.
Ingredients vary with each Prevacid version. Check label ingredients for allergies before taking Prevacid.
Patients with PKE should talk with their doctor before taking Prevacid SoluTabs.
People Should Talk with Their Doctor Before Taking Prevacid If They Have:
- Low blood magnesium
- Liver disease
- Lupus
- Allergies to any PPI or PPI ingredient
- Phenylketonuria (PKE)
Women who are pregnant or breastfeeding should consult their doctor before taking Prevacid or any other medication.
Prevacid Drug Interactions
Prevacid interactions can happen with 290 other drugs or dietary supplements. People should tell their doctor what drugs they take before starting Prevacid.
Some Prevacid interactions can happen with things as common as aspirin or fish oil.
Prevacid Drug Interactions
| Drug | Side Effect |
|---|---|
| HIV Antiretrovirals (including rilpivirine, atazanavir, delavirdine and nelfinavir) | Decreases or increases drug effects |
| Warfarin | Increases risk of bleeding or death |
| Methotrexate | Can lead to methotrexate toxicity |
| Digoxin | Increased exposure |
| Theophylline | Increases clearance of theophylline |
| Drugs dependent on gastric pH for absorption (iron salts) | Reduces absorption |
| Antibiotics (clarithromycin and amoxicillin) | Possible serious adverse reactions, including potentially fatal arrhythmias |
| Tacrolimus | Increases drug’s effects |
CYP2C19 or CYP3A4 inducers (St. John’s Wort, rifampin and Ritonavir-containing products) | Decreases Prevacid effects |
| CYP2C19 or CYP3A4 inhibitors (voriconazole) | Increases Prevacid effects |
| Sucralfate | Decreases and delays Prevacid absorption |
| Clopidogrel (Plavix) | Decreases effectiveness of Plavix, can increase heart attack risk |
| Aminophylline | May increase aminophylline levels by slowing metabolism, may result in aminophylline toxicity in extremely high doses (interaction is unlikely and effects are minor) |
Prevacid Facts
Please seek the advice of a medical professional before making health care decisions.
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Pepcid AC Advanced Patient Information
Generic name: famotidine [ fam-OH-ti-deen ]
Drug class: h3 antagonists
Medically reviewed by Drugs.
com. Last updated on Feb 20, 2023.
Uses for Pepcid AC
Famotidine is used to treat stomach ulcers (gastric and duodenal), erosive esophagitis (heartburn or acid indigestion), and gastroesophageal reflux disease (GERD). GERD is a condition where the acid in the stomach washes back up into the esophagus. It is also used to treat certain conditions where there is too much acid in the stomach (eg, Zollinger-Ellison syndrome, multiple endocrine neoplasia).
Famotidine belongs to the group of medicines known as histamine h3-receptor antagonists or h3-blockers. It works by decreasing the amount of acid produced by the stomach.
This medicine is available with your doctor’s prescription and also without a prescription. For the prescription form, there is more medicine in each tablet. Your doctor will have special instructions on the proper use and dose for your medical problem.
Before using Pepcid AC
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do.
This is a decision you and your doctor will make. For this medicine, the following should be considered:
Allergies
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Pediatric
Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of famotidine in children weighing 40 kilograms (kg) or more. Safety and efficacy have not been established in children to treat conditions causing too much stomach acid and to prevent an ulcer from coming back.
Geriatric
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of famotidine in the elderly. However, elderly patients are more likely to have age-related kidney problems, which may require an adjustment in the dose for patients receiving famotidine.
Breast Feeding
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with Medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Bepridil
- Cisapride
- Dronedarone
- Levoketoconazole
- Mesoridazine
- Pimozide
- Piperaquine
- Saquinavir
- Sparfloxacin
- Terfenadine
- Thioridazine
- Ziprasidone
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Acalabrutinib
- Adagrasib
- Amiodarone
- Amisulpride
- Amprenavir
- Anagrelide
- Apomorphine
- Aripiprazole
- Aripiprazole Lauroxil
- Arsenic Trioxide
- Atazanavir
- Buprenorphine
- Bupropion
- Buserelin
- Ceritinib
- Chloroquine
- Citalopram
- Clarithromycin
- Clofazimine
- Clothiapine
- Clozapine
- Crizotinib
- Dabrafenib
- Dasatinib
- Degarelix
- Delamanid
- Delavirdine
- Deslorelin
- Deutetrabenazine
- Dexmedetomidine
- Domperidone
- Donepezil
- Efavirenz
- Encorafenib
- Entrectinib
- Erlotinib
- Escitalopram
- Fexinidazole
- Fingolimod
- Fluconazole
- Fluoxetine
- Formoterol
- Fosamprenavir
- Foscarnet
- Fostemsavir
- Gefitinib
- Glasdegib
- Gonadorelin
- Goserelin
- Histrelin
- Hydroxychloroquine
- Hydroxyzine
- Infigratinib
- Inotuzumab Ozogamicin
- Ivabradine
- Ivosidenib
- Ketoconazole
- Ledipasvir
- Lefamulin
- Lenvatinib
- Leuprolide
- Levofloxacin
- Lofexidine
- Macimorelin
- Methadone
- Metronidazole
- Mirtazapine
- Mobocertinib
- Moxifloxacin
- Nafarelin
- Neratinib
- Octreotide
- Ondansetron
- Osilodrostat
- Osimertinib
- Oxaliplatin
- Ozanimod
- Pacritinib
- Panobinostat
- Pasireotide
- Pazopanib
- Phenobarbital
- Pimavanserin
- Pitolisant
- Ponesimod
- Posaconazole
- Primidone
- Quetiapine
- Relugolix
- Ribociclib
- Rilpivirine
- Secretin Human
- Selpercatinib
- Sertraline
- Sevoflurane
- Siponimod
- Solifenacin
- Sotalol
- Sotorasib
- Sparsentan
- Sulpiride
- Sunitinib
- Tacrolimus
- Tizanidine
- Tolazoline
- Trazodone
- Triclabendazole
- Triptorelin
- Vandetanib
- Vardenafil
- Vemurafenib
- Vilanterol
- Vinflunine
- Vismodegib
- Voclosporin
- Zuclopenthixol
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you.
If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Cefditoren Pivoxil
- Cefpodoxime Proxetil
- Cyclosporine
Interactions with Food/Tobacco/Alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Kidney disease, moderate to severe—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
Proper use of Pepcid AC
Take this medicine exactly as directed by your doctor or as directed on the package.
Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. To do so may increase the chance of side effects.
Keep using this medicine for the full time of treatment, even if you begin to feel better.
You may take this medicine with or without food.
Measure the oral liquid with a marked measuring spoon or medicine cup. The average household teaspoon may not hold the right amount of liquid.
Dosing
The dose of this medicine will be different for different patients. Follow your doctor’s orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage forms (suspension, tablets):
- To prevent an ulcer from coming back:
- Adults—20 milligrams (mg) once a day.
- Children—Use and dose must be determined by your doctor.
- To treat erosive esophagitis (heartburn):
- Adults and children weighing 40 kilograms (kg) or more—20 milligrams (mg) 1 or 2 times per day, at the morning and at bedtime, or 40 mg once a day at bedtime for up to 12 weeks.
- Children weighing less than 40 kg—Use and dose be determined by your doctor.
- To treat gastroesophageal reflux disease (GERD):
- Adults and children weighing 40 kilograms (kg) or more—20 milligrams (mg) 2 times per day, in the morning and at bedtime for up to 6 weeks.
- Children weighing less than 40 kg—Use and dose be determined by your doctor.
- To treat stomach ulcers:
- Adults and children weighing 40 kilograms (kg) or more—20 milligrams (mg) 2 times per day, at the morning and at bedtime, or 40 mg once a day at bedtime for up to 8 weeks.

- Children weighing less than 40 kg—Use and dose be determined by your doctor.
- Adults and children weighing 40 kilograms (kg) or more—20 milligrams (mg) 2 times per day, at the morning and at bedtime, or 40 mg once a day at bedtime for up to 8 weeks.
- To treat too much stomach acid (Zollinger-Ellison syndrome):
- Adults—20 milligrams (mg) every 6 hours. Your doctor may adjust your dose as needed.
- Children—Use and dose must be determined by your doctor.
- To prevent an ulcer from coming back:
Missed Dose
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Storage
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Throw away any unused oral liquid after 30 days.
Precautions while using Pepcid AC
It is very important that your doctor check your or your child’s progress at regular visits to make sure this medicine is working properly.
Blood and urine tests may be needed to check for unwanted effects.
If your condition does not improve, or if it become worse, check with your doctor.
Check with your doctor right away if you have the following symptoms: confusion, delirium, hallucinations, disorientation, agitation, seizures, or unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness. These are more likely to occur if you are older or if you have a kidney disease.
Contact your doctor right away if you have any changes to your or your child’s heart rhythm. You or your child might feel dizzy or faint, or you or your child might have a fast, pounding, or uneven heartbeat. Make sure your doctor knows if you had a heart rhythm problem, such as QT prolongation.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Side Effects of Pepcid AC
Along with its needed effects, a medicine may cause some unwanted effects.
Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Rare
- Anxiety
- bleeding gums
- blistering, peeling, or loosening of the skin
- blood in the urine or stools
- bloody, black, or tarry stools
- cough
- difficulty breathing
- discouragement
- fast, irregular, pounding, or racing heartbeat or pulse
- feeling sad or empty
- irritability
- lack of appetite
- loss of interest or pleasure
- noisy breathing
- pinpoint red spots on the skin
- seeing, hearing, or feeling things that are not there
- seizures
- swelling around the eyes
- tightness in the chest
- trouble concentrating
- trouble sleeping
- unusual bleeding or bruising
Incidence not known
- Agitation
- blistering, peeling, or loosening of the skin
- burning, crawling, itching, numbness, prickling, “pins and needles”, or tingling feelings
- chest pain
- chills
- clay-colored stools
- dark urine
- diarrhea
- difficulty swallowing
- dizziness or fainting
- fever
- general feeling of tiredness or weakness
- headache
- high fever
- hives, itching, skin rash
- hoarseness
- joint or muscle pain
- large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
- light-colored stools
- lower back or side pain
- nausea
- painful or difficult urination
- pale skin
- puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
- red skin lesions, often with a purple center
- red, irritated eyes
- sore throat
- sores, ulcers, or white spots in the mouth or on the lips
- stomach pain
- swollen glands
- unpleasant breath odor
- unusual tiredness or weakness
- upper right abdominal pain
- vomiting of blood
- yellow eyes or skin
Some side effects may occur that usually do not need medical attention.
These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
- Difficulty having a bowel movement
Rare
- Bad, unusual, or unpleasant (after) taste
- bone or muscle pain
- change in taste
- continuing ringing or buzzing or other unexplained noise in the ears
- decreased interest in sexual intercourse
- difficulty in moving
- dry mouth
- dry skin
- feeling of warmth
- hearing loss
- inability to have or keep an erection
- lack or loss of strength
- loss in sexual ability, desire, drive, or performance
- muscle pain or stiffness
- redness of the face, neck, arms and occasionally, upper chest
- redness of the white part of the eyes
- stomach discomfort
- unusual drowsiness
Other side effects not listed may also occur in some patients.
If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Frequently asked questions
- Is famotidine safer than omeprazole for heartburn?
- Can you take famotidine long term?
- Can I take omeprazole in the morning and famotidine at night?
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Medical Disclaimer
Alternating current and its characteristics
Contents
With a constant voltage, everything is simple, the current will at any time be equal to the voltage divided by the resistance, and the power will be the product of the current and the voltage. With alternating current, everything is much more interesting.
Let’s start with the fact that resistances with alternating current are active and reactive. What is their difference?
Active resistances are a resistor, a light bulb, any heating element such as an electric kettle. If there are only active resistances in the AC circuit, then everything will be as simple with it as with a constant one. And all because the current at each moment of time will be calculated according to Ohm’s law, which means that the current will change synchronously with the voltage, as in the graph below:
Figure 1 – Graph of active resistance.
Reactances are elements such as capacitances and inductances.
At some moments they “interfere” with the current, at others, on the contrary, they help. This is reminiscent of trying to walk from the shore along the bottom of the sea in a strong swell. The wave sometimes helps to go, sometimes it hinders, but does not slow down progress in general.
capacitive reactance. A capacitance or capacitor is an element that can be charged, storing electrical voltage, and then give it to the circuit. In AC circuits, this causes the current to “lead” the voltage. After all, while the voltage rises, the capacitor is charged, and the current in the circuit is maximum. And when the voltage reaches its maximum, the capacitor is already fully charged and the current will be zero.
Figure 2 – Graph of capacitive reactance.
Inductive reactance works in reverse. Inductance is an electromagnet, a transformer, a choke, an electric motor, in general, everything where there are coils or windings. Inductance has inertia, that is, it can store current, which means that while the voltage is growing, the current has not yet accelerated and will be minimal.
And the maximum current will reach only by the moment when the voltage has already passed the upper point and begins to decline. That is, the current is “delayed”.
Figure 3 – Plot of inductive reactance.
Thus, we see that only active consumers irrevocably consume power from the network. Reactive ones either consume or return energy to the network.
Therefore, power is distinguished between active, reactive and total.
Apparent power is considered in the same way as for direct current and is equal to the product of current and voltage. Therefore, the apparent power is measured in Volt-Amps or VA. The apparent power consists of active and reactive, and they add up geometrically in the form of a triangle:
Figure 4 – Power Triangle.
Active power is measured in Watts (W) – this is the power that is consumed directly by the consumer and converted into other types of energy, such as heat, light, sound, mechanical energy.
Reactive power is either consumed or returned, so household electricity meters do not take it into account, however, it also “walks” along the wires, which means that their thickness should also take into account these parasitic currents. In addition, reactive power, passing through the wires, causes them to heat up, acting as additional active consumers.
To determine the share of active power in the total, there is a value called cosf, PF or power factor. This is the cosine of the same phase angle in the power triangle, equal to the active power divided by the total. The closer it is to 1, the less the reactive component. To visualize this whole picture, imagine a cold mug of beer. If half of the total poured volume is foam, then in order to drink 0.5 liters of drink, we need a liter mug:
Figure 5 – Plot of power factor.
Questions for self-test:
- There is an electric kettle for 220V, 2000W. What size copper wire is needed for it?
- There is a 220V device consuming 3000W and having PF=0.


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