OverviewDosageSide EffectsInteractionsHalf-Life

The following serious adverse reactions of famotidine are discussed in greater detail in other sections:

  • Headache
  • Dizziness
  • Constipation
  • Diarrhea

Adverse Reactions

Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Famotidine tablets were studied in 7 US and international placebo- and active-controlled trials in approximately 2500 patients. A total of 1442 patients were treated with famotidine tablets, including 302 treated with 40 mg twice daily, 456 treated with 20 mg twice daily, 461 treated with 40 mg once daily, and 396 treated with 20 mg once daily. The population was 17-91 years old, fairly well distributed between gender and race; however, the predominant race treated was Caucasian.

The following adverse reactions occurred in greater than or equal to 1% of famotidine tablets-treated patients: headache, dizziness, and constipation.

The following other adverse reactions were reported in less than 1% of patients in clinical trials:

Body as a Whole: fever, asthenia, fatigue

Cardiovascular: palpitations

Gastrointestinal: elevated liver enzymes, vomiting, nausea, abdominal discomfort, anorexia, dry mouth

Hematologic: thrombocytopenia

Hypersensitivity: orbital edema, rash, conjunctival injection, bronchospasm

Musculoskeletal: musculoskeletal pain, arthralgia

Nervous System/Psychiatric: seizure, hallucinations, depression, anxiety, decreased libido, insomnia, somnolence

Skin: pruritus, dry skin, flushing

Special Senses: tinnitus, taste disorder

Other: impotence

Post-marketing Experience

The following adverse reactions have been identified during post-approval use of famotidine. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Cardiovascular: arrhythmia, AV block, prolonged QT interval

Gastrointestinal: cholestatic jaundice, hepatitis

Hematologic: agranulocytosis, pancytopenia, leukopenia

Hypersensitivity: anaphylaxis, angioedema, facial edema, urticaria

Musculoskeletal: rhabdomyolysis, muscle cramps

Nervous System/Psychiatric: confusion, agitation, paresthesia

Respiratory: interstitial pneumonia

Skin: toxic epidermal necrolysis/Stevens-Johnson syndrome

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.


More About Famotidine

Below are the general guidelines for dosing famotidine. Note that these dosages may be adjusted on a case-by-case basis for individual patients by a provider. Always follow your prescribing physician’s instructions for taking famotidine.

The following information comes from DailyMed, the official FDA label information provider for drugs.

What if I miss a dose of Famotidine?

If you miss a dose of famotidine, take it as soon as you can. If it’s almost time for your next dose, however, skip the missed dose and revert back to your regular schedule. Be sure not to double your doses.

What if I overdose on Famotidine?

The types of adverse reactions in overdosage of famotidine tablets are similar to the adverse reactions encountered with the use of recommended dosages.

In the event of overdosage, treatment should be symptomatic and supportive. Unabsorbed material should be removed from the gastrointestinal tract, the patient should be monitored, and supportive therapy should be employed.

Due to low binding to plasma proteins, famotidine is eliminated by hemodialysis. There is limited experience on the usefulness of hemodialysis as a treatment for famotidine tablets overdosage.

How is Famotidine administered?

Administration Instructions

  • Take famotidine tablets once daily before bedtime or twice daily in the morning and before bedtime, as recommended.
  • Famotidine tablets may be taken with or without food.
  • Famotidine tablets may be given with antacids.

How is Famotidine supplied?

Famotidine Tablets USP, 20 mg are available as beige, round, unscored, film-coated tablets, debossed with “5728” on one side and “TEVA” on the other side, containing 20 mg famotidine, packaged in bottles of 100 (NDC 0172-5728-60), 500 (NDC 0172-5728-70) and 1000 (NDC 0172-5728-80) tablets.

Famotidine Tablets USP, 40 mg are available as tan, round, unscored, film-coated tablets, debossed with “5729” on one side and “TEVA” on the other side, containing 40 mg famotidine, packaged in bottles of 100 (NDC 0172-5729-60) and 500 (NDC 0172-5729-70) tablets.

Dispense in a well-closed, light-resistant container as defined in the USP, with a child-resistant closure (as required).

Store at 20° to 25°C (68° to 77°F) [See USP Controlled Room Temperature].

Avoid storage of famotidine tablets at temperatures above 40°C (104°F).

KEEP THIS AND ALL MEDICATIONS OUT OF THE REACH OF CHILDREN.

Disclaimer: this article does not constitute or replace medical advice. If you have an emergency or a serious medical question, please contact a medical professional or call 911 immediately. To see our full medical disclaimer, visit our Terms of Use page.


More About Famotidine

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