Famotidine (Page 2 of 6)

2.3 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 [see Clinical Pharmacology ( 12.3)] .
  • Famotidine tablets may be given with antacids.


  • 20 mg tablets: beige, round, unscored, film-coated tablets, debossed with “5728” on one side and “TEVA” on the other side.
  • 40 mg tablets: tan, round, unscored, film-coated tablets, debossed with “5729” on one side and “TEVA” on the other side.


Famotidine tablets are contraindicated in patients with a history of serious hypersensitivity reactions (e.g., anaphylaxis) to famotidine or other histamine-2 (H 2 ) receptor antagonists.


5.1 Central Nervous System Adverse Reactions

Central nervous system (CNS) adverse reactions, including confusion, delirium, hallucinations, disorientation, agitation, seizures, and lethargy, have been reported in elderly patients and patients with moderate and severe renal impairment treated with famotidine tablets. Since famotidine blood levels are higher in patients with renal impairment than in patients with normal renal function, dosage adjustments are recommended in patients with renal impairment [see Dosage and Administration ( 2.2), Clinical Pharmacology ( 12.3)].

5.2 Concurrent Gastric Malignancy

In adults, symptomatic response to therapy with famotidine tablets does not preclude the presence of gastric malignancy. Consider evaluation for gastric malignancy in adult patients who have a suboptimal response or an early symptomatic relapse after completing treatment with famotidine tablets.


6.1 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 was studied in 7 US and international placebo- and active-controlled trials in approximately 2500 patients [see Clinical Studies ( 14)] . 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

6.2 Postmarketing 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


7.1 Drugs Dependent on Gastric pH for Absorption

Famotidine can reduce the absorption of other drugs, due to its effect on reducing intragastric acidity, leading to loss of efficacy of the concomitant drug.

Concomitant administration of famotidine tablets with dasatinib, delavirdine mesylate, cefditoren, and fosamprenavir is not recommended.

See the prescribing information for other drugs dependent on gastric pH for absorption for administration instructions, including atazanavir, erlotinib, ketoconazole, itraconazole, ledipasvir/sofosbuvir, nilotinib, and rilpivirine.

7.2 Tizanidine (CYP1A2 Substrate)

Although not studied clinically, famotidine is considered a weak CYP1A2 inhibitor and may lead to substantial increases in blood concentrations of tizanidine, a CYP1A2 substrate. Avoid concomitant use with famotidine tablets. If concomitant use is necessary, monitor for hypotension, bradycardia or excessive drowsiness. Refer to the full prescribing information for tizanidine.


8.1 Pregnancy

Risk Summary

Available data with H 2 -receptor antagonists, including famotidine, in pregnant women are insufficient to establish a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes. In animal reproduction studies, no adverse development effects were observed with oral administration of famotidine at doses up to approximately 243 and 122 times, respectively, the recommended human dose of 80 mg per day for the treatment of erosive esophagitis (se e Data).

The estimated background risk for major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.


Animal Data

Reproductive studies have been performed in rats and rabbits at oral doses of up to 2000 and 500 mg/kg/day, respectively, and in both species at intravenous doses of up to 200 mg/kg/day, and have revealed no significant evidence of impaired fertility or harm to the fetus due to famotidine tablets. While no direct fetotoxic effects have been observed, sporadic abortions occurring only in mothers displaying marked decreased food intake were seen in some rabbits at oral doses of 200 mg/kg/day (about 49 times the recommended human dose of 80 mg per day, based on body surface area) or higher. There are, however, no adequate or well-controlled studies in pregnant women. Because animal reproductive studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.

8.2 Lactation

Risk Summary

There are limited data available on the presence of famotidine in human breast milk. There were no effects on the breastfed infant. There are no data on famotidine effects on milk production. Famotidine is present in the milk of lactating rats (see Data).

The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for famotidine and any potential adverse effects on the breastfed child from famotidine tablets or from the underlying maternal condition.


Animal Data

Transient growth depression was observed in young rats suckling from mothers treated with maternotoxic doses of famotidine at least 600 times the usual human dose.

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