What is Prevacid used for. How does Prevacid work. What are the potential side effects of Prevacid. How does Prevacid compare to other heartburn medications. What lawsuits have been filed related to Prevacid. How should Prevacid be taken properly.

Understanding Prevacid: A Powerful Proton Pump Inhibitor

Prevacid (lansoprazole) is a proton pump inhibitor (PPI) medication used to treat conditions related to excess stomach acid. As a PPI, it works by decreasing acid production in the stomach, allowing time for healing of the stomach lining and esophagus. The FDA approved Prevacid in 1995, and it is available in both prescription and over-the-counter formulations.

Are PPIs like Prevacid safe for long-term use? While Prevacid is generally intended for short-term treatment lasting 10 days to 12 weeks, some patients use it for extended periods. However, studies have linked long-term PPI use to several potential health risks that patients should be aware of.

FDA-Approved Uses for Prevacid

Prevacid is approved to treat several gastrointestinal conditions involving excess stomach acid production. The main FDA-approved uses include:

• Treating and maintaining duodenal ulcers
• Treating certain types of gastric ulcers
• Managing symptoms of gastroesophageal reflux disease (GERD)
• Treating and maintaining healing of erosive esophagitis
• Treating Zollinger-Ellison syndrome and other hypersecretory conditions
• Eradicating H. pylori bacteria when used with antibiotics

Can Prevacid provide instant heartburn relief? No, Prevacid is not intended for quick symptom relief. It may take up to four days of regular use before acid reflux symptoms improve. For faster relief, over-the-counter antacids may be more appropriate.

How Prevacid Works to Reduce Stomach Acid

Prevacid’s active ingredient lansoprazole belongs to the proton pump inhibitor class of drugs. These medications work by:

1. Binding to proton pumps in the stomach lining
2. Blocking the final step of acid production
3. Decreasing the overall amount of acid released into the stomach

By reducing stomach acid, Prevacid allows time for damaged tissue in the esophagus and stomach to heal. It can also prevent further irritation and complications like ulcers from developing.

How long does it take for Prevacid to start working? Unlike fast-acting antacids, Prevacid may take 1-4 days of consistent use to reach full effect in reducing stomach acid production. Patients should follow dosing instructions carefully for best results.

Prevacid vs Other Heartburn Medications

How does Prevacid compare to other common heartburn treatments? While both reduce stomach acid, proton pump inhibitors like Prevacid differ from histamine H2 blockers in several ways:

While H2 blockers like Pepcid provide faster relief, PPIs like Prevacid are generally more effective for treating severe acid reflux and ulcers when used as directed.

Potential Side Effects and Risks of Prevacid

What are the most common side effects of Prevacid? Short-term use of Prevacid is generally well-tolerated. When side effects occur, they tend to be mild and may include:

• Headache
• Nausea
• Diarrhea
• Stomach pain
• Constipation

However, long-term use of Prevacid and other PPIs has been associated with more serious health risks in some studies. Potential severe side effects linked to prolonged PPI use include:

• Kidney problems including acute interstitial nephritis
• Increased risk of bone fractures
• Vitamin B12 deficiency
• Clostridium difficile infections
• Lupus-like autoimmune reactions
• Low magnesium levels

Patients taking Prevacid should be aware of warning signs that may indicate a serious reaction. When should you call your doctor about Prevacid side effects? Seek immediate medical attention for symptoms like:

• Severe or bloody diarrhea
• Unusual heart rhythm
• Muscle spasms or weakness
• Seizures
• Decreased urine output

FDA Warnings for Prevacid and Other PPIs

The U.S. Food and Drug Administration has issued several safety communications regarding potential risks associated with long-term use of proton pump inhibitors like Prevacid. Key FDA warnings include:

• 2010: Increased risk of fractures with long-term, high-dose PPI use
• 2011: Low serum magnesium levels with prolonged PPI treatment
• 2012: Clostridium difficile-associated diarrhea risk
• 2014: Acute interstitial nephritis
• 2016: Lupus erythematosus events

These warnings emphasize the importance of using PPIs only as directed and for the shortest duration necessary to achieve treatment goals. Patients should discuss the benefits and risks of long-term PPI use with their healthcare provider.

Prevacid Lawsuits and Legal Actions

Have there been lawsuits related to Prevacid side effects? Yes, thousands of patients have filed lawsuits against manufacturers of proton pump inhibitors, including Prevacid, alleging they suffered kidney damage after long-term use of these medications.

As of July 2019, over 12,775 PPI lawsuits were pending in a multidistrict litigation (MDL) in New Jersey federal court. The lawsuits claim drug makers failed to adequately warn about potential kidney risks associated with long-term PPI use.

What injuries are being claimed in Prevacid lawsuits? The main kidney-related complications alleged in the legal actions include:

• Acute interstitial nephritis (AIN)
• Chronic kidney disease
• End-stage renal disease
• Kidney failure requiring dialysis or transplant

The litigation is ongoing, and no settlements or verdicts have been reached as of 2024. Patients who believe they may have suffered kidney damage from Prevacid use should consult with a qualified attorney to understand their legal options.

Proper Use and Precautions for Taking Prevacid

How should Prevacid be taken for best results and safety? Follow these guidelines when using Prevacid:

• Take Prevacid exactly as prescribed by your doctor or as directed on the OTC label
• Swallow delayed-release capsules whole; do not crush or chew
• For difficulty swallowing, Prevacid SoluTab can be dissolved on the tongue
• Take on an empty stomach before eating
• Complete the full course of treatment, even if symptoms improve
• Do not take for more than 14 days in a row without consulting a doctor

What precautions should be taken when using Prevacid? Inform your healthcare provider about all medications and supplements you take, as Prevacid may interact with certain drugs. Use caution when taking Prevacid if you:

• Are pregnant or breastfeeding
• Have liver disease
• Are over 50 years old
• Have low magnesium levels
• Are at increased risk for osteoporosis

Regular monitoring of kidney function, magnesium levels, and bone density may be recommended for patients on long-term PPI therapy. Always consult your doctor before starting or stopping any medication regimen.

Alternatives to Prevacid for Acid Reflux Management

For patients concerned about potential risks of long-term PPI use, are there alternatives to Prevacid for managing acid reflux? Several options may be considered:

• H2 blockers like famotidine (Pepcid) for less severe symptoms
• Antacids for occasional heartburn relief
• Lifestyle modifications (diet changes, weight loss, avoiding trigger foods)
• Elevating the head of the bed
• Quitting smoking
• Stress reduction techniques

Some patients may benefit from a combination of medication and lifestyle changes. Work with your healthcare provider to develop an individualized treatment plan that balances symptom relief with long-term safety considerations.

The Future of Acid Reflux Treatment

As concerns about long-term PPI use continue to emerge, what does the future hold for acid reflux treatment? Researchers are exploring several promising avenues:

• New classes of acid-suppressing medications with improved safety profiles
• Advancements in minimally invasive surgical techniques
• Personalized medicine approaches based on genetic factors
• Novel drug delivery systems for more targeted therapy
• Probiotic and microbiome-based treatments

While PPIs like Prevacid remain an important treatment option for many patients, ongoing research may lead to safer and more effective alternatives in the coming years. Patients should stay informed about emerging treatments and discuss new options with their healthcare providers as they become available.

In conclusion, Prevacid (lansoprazole) is a potent medication for treating acid-related gastrointestinal conditions. While effective for short-term use, patients and healthcare providers must weigh the benefits against potential risks associated with long-term PPI therapy. By understanding how Prevacid works, its proper use, and potential side effects, patients can make informed decisions about their acid reflux treatment in consultation with their doctors.

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

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.
  • 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.

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.

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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:

1. There is an electric kettle for 220V, 2000W. What size copper wire is needed for it?
2. There is a 220V device consuming 3000W and having PF=0.