DrugLib.com — Drug Information Portal

Rx drug information, pharmaceutical research, clinical trials, news, and more

Fluxid (Famotidine) - Warnings and Precautions




Symptomatic response to therapy with famotidine does not preclude the presence of gastric malignancy.

Patients with Moderate or Severe Renal Insufficiency

Since CNS adverse effects have been reported in patients with moderate and severe renal insufficiency, longer intervals between doses or lower doses may need to be used in patients with moderate (creatinine clearance <50 mL/min) or severe (creatinine clearance <10 mL/min) renal insufficiency to adjust for the longer elimination half-life of famotidine (see CLINICAL PHARMACOLOGY IN ADULTS and DOSAGE AND ADMINISTRATION).

Information for patients

Patients should be instructed not to remove FLUXID™ Tablets from the bottle until just prior to dosing. With dry hands, the tablet should be removed from the bottle and immediately placed on the tongue to dissolve and be swallowed with the saliva. The tablet typically disintegrates in less than 2 minutes.

Drug interactions

No drug interactions have been identified. Studies with famotidine in man, in animal models, and in vitro have shown no significant interference with the disposition of compounds metabolized by the hepatic microsomal enzymes, e.g., cytochrome P450 system. Compounds tested in man include warfarin, theophylline, phenytoin, diazepam, aminopyrine and antipyrine. Indocyanine green as an index of hepatic drug extraction has been tested and no significant effects have been found.

Carcinogenesis, mutagenesis, impairment of fertility

In a 106 week study in rats and a 92 week study in mice given oral doses of up to
2000 mg/kg/day (approximately 405 times in rats, and 203 times in mice, the recommended maximum human dose based on body surface area), there was no evidence of carcinogenic potential for famotidine.

Famotidine was negative in the Ames test, the mouse micronucleus test and the mouse chromosomal aberration test.

In studies with rats given oral doses of up to 2000 mg/kg/day (approximately 405 times the recommended maximum human dose based on body surface area), fertility and reproductive performance were not affected.

Pregnancy. Teratogenic Effects: Pregnancy Category B

Reproductive studies have been performed at oral doses of up to 2000 mg/kg/day in rat (approximately 405 times the recommended maximum human dose based on body surface area) and 500 mg/kg/day in rabbit (approximately 203 times the recommended maximum human dose based on body surface area), and have revealed no significant evidence of impaired fertility or harm to the fetus due to famotidine. 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.

Nursing mothers

Famotidine is detectable in human milk. Transient growth depression was observed in young rats suckling from mothers treated with famotidine. Because of the potential for serious adverse reactions in nursing infants from famotidine, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Patients 6-16 years of age

Use of famotidine in pediatric patients 6-16 years of age is supported by evidence from adequate and well-controlled studies of famotidine in adults, and by the following studies in pediatric patients: In published studies in small numbers of pediatric patients 1-15 years of age, clearance of famotidine was similar to that seen in adults. In pediatric patients 11-15 years of age, oral doses of 0.5 mg/kg were associated with a mean area under the curve (AUC) similar to that seen in adults treated orally with 40 mg. Limited published studies also suggest that the relationship between serum concentration and acid suppression is similar in pediatric patients 1-15 years of age as compared with adults. These studies suggest a starting dose for pediatric patients 6 - 16 years of age as follows:

Gastroesophageal Reflux Disease with or without esophagitis including erosions and
- 1.0 mg/kg/day p.o. divided b.i.d. up to 40 mg b.i.d.

While published uncontrolled studies suggest effectiveness of famotidine in the treatment of gastroesophageal reflux disease, data in pediatric patients are insufficient to establish percent response with dose and duration of therapy. Therefore, treatment duration (initially based on adult duration recommendations) and dose should be individualized based on clinical response and/or pH determination (gastric or esophageal) and endoscopy. Published uncontrolled clinical studies in pediatric patients have employed doses up to 2 mg/kg/day for GERD with or without esophagitis including erosions and ulcerations.

Geriatric use

Of the 4,966 subjects in clinical studies who were treated with famotidine, 488 subjects (9.8%) were 65 and older, and 88 subjects (1.7%) were greater than 75 years of age. No overall differences in safety or effectiveness were observed between these subjects and younger subjects. However, greater sensitivity of some older individuals cannot be ruled out.

No dosage adjustment is required based on age (see CLINICAL PHARMACOLOGY IN ADULTS, Pharmacokinetics). This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function. Dosage adjustment in the case of moderate or severe renal impairment is necessary (see PRECAUTIONS, Patients with Moderate or Severe Renal Insufficiency and DOSAGE AND ADMINISTRATION, Dosage Adjustment for Patients with Moderate or Severe Renal Insufficiency).

Page last updated: 2006-11-07

-- advertisement -- The American Red Cross
Home | About Us | Contact Us | Site usage policy | Privacy policy

All Rights reserved - Copyright DrugLib.com, 2006-2017