Pepcid 40 mg Tablets

Brand Name

The medication is marketed under the brand name Pepcid, a well-established label in the realm of gastrointestinal acid suppression and relief.

International Nonproprietary Name (INN)

The active ingredient in this product is identified globally as famotidine, a name standardized for consistency across international pharmacological practices.

Form of Release

Pepcid is available in multiple forms, including oral tablets, chewable tablets, orally disintegrating tablets, and an intravenous solution. Tablets come in strengths of 10 mg, 20 mg, and 40 mg, chewable and disintegrating tablets match these doses, and the injectable form provides 10 mg per mL, typically in vials for hospital use.

Composition

Each tablet of Pepcid contains famotidine as the primary active substance, with dosages of 10 mg, 20 mg, or 40 mg. The formulation includes several inactive ingredients, such as microcrystalline cellulose, which provides structural support, and pregelatinized starch, acting as a binder. Additional excipients like magnesium stearate serve as lubricants, while the chewable form includes mannitol and aspartame for taste, and the disintegrating tablets contain citric acid for rapid dissolution. The intravenous solution includes L-aspartic acid and sodium chloride for stability and isotonicity, ensuring effective delivery across all administration routes.

Pharmacologic Properties

Pharmacodynamics

Pepcid functions as a histamine H2-receptor antagonist, exerting its effects by competitively blocking H2 receptors on gastric parietal cells. This inhibition reduces histamine-stimulated gastric acid secretion, decreasing both basal and meal-induced acid output, which elevates intragastric pH and alleviates acid-related symptoms. Its selective action provides rapid relief from heartburn and promotes healing in conditions like ulcers by reducing acid-mediated damage to mucosal tissues.

The medication also inhibits pepsin secretion indirectly by lowering acid levels, though it does not affect gastrin release or gastric motility significantly. Clinical studies demonstrate its ability to reduce acid secretion by 70–90% within 1–2 hours, with effects lasting up to 12 hours per dose. It lacks anticholinergic or central nervous system effects, focusing solely on gastric acid control. This targeted mechanism underpins its efficacy in managing acid-related disorders efficiently.

Pharmacokinetics

Following oral administration, Pepcid is absorbed from the gastrointestinal tract, with peak plasma concentrations reached within 1 to 3 hours. Bioavailability ranges from 40–45%, reduced by first-pass metabolism, and food slightly delays absorption without altering extent. The drug binds to plasma proteins at approximately 15–20%, distributing widely to tissues, including the stomach, kidneys, and liver.

Metabolism is minimal, with about 25–30% processed in the liver into an inactive sulfoxide metabolite, while the majority remains unchanged. The half-life ranges from 2.5 to 4 hours, supporting once- or twice-daily dosing. Elimination is predominantly renal, with 65–70% excreted unchanged in urine and the remainder as metabolites, with minor fecal clearance, reflecting its reliance on kidney function for clearance.

Indications for Use

Pepcid is prescribed for the treatment of active duodenal ulcers in adults, promoting healing and relieving pain within 4–8 weeks. It is also indicated for maintenance therapy in healed duodenal ulcers to prevent recurrence, offering sustained acid suppression. The medication manages gastroesophageal reflux disease (GERD), including erosive esophagitis, addressing heartburn and esophageal irritation.

It treats benign gastric ulcers and provides symptomatic relief in non-erosive GERD or dyspepsia caused by excess acid. In hospital settings, intravenous use is indicated for pathological hypersecretory conditions like Zollinger-Ellison syndrome or for patients unable to take oral medications. Over-the-counter formulations address occasional heartburn, acid indigestion, or sour stomach, making it versatile for both prescription and self-care use.

Contraindications

Pepcid is contraindicated in patients with known hypersensitivity to famotidine, other H2-receptor antagonists, or any formulation component, such as aspartame in chewables, where reactions could range from rash to anaphylaxis. It is also prohibited in those requiring immediate acid suppression unavailable via oral forms, unless intravenous administration is feasible.

Use is restricted in patients with a history of severe allergic reactions to the drug class or in those with undiagnosed gastrointestinal bleeding, as it may mask underlying conditions like malignancy. Severe renal impairment does not strictly contraindicate it, but caution is essential. The medication should not be used in neonates or infants under 1 year for intravenous forms due to limited safety data.

Method of Administration and Dosage

Administration Guidelines

The tablets should be taken orally, swallowed whole with water, with or without food, though nighttime dosing enhances overnight acid control. Chewable tablets require chewing before swallowing, and disintegrating tablets dissolve on the tongue, followed by water if needed. Intravenous doses are administered by healthcare professionals over 2–15 minutes. Timing aligns with symptom onset or prevention needs for optimal relief.

Dosage for Adults and Children

For adults with active duodenal ulcers, the typical dose of Pepcid is 40 mg once daily at bedtime or 20 mg twice daily for 4–8 weeks. Maintenance therapy uses 20 mg once daily. GERD with esophagitis requires 20–40 mg twice daily for 6–12 weeks, while symptomatic GERD uses 20 mg twice daily for up to 6 weeks. Over-the-counter use is 10–20 mg as needed, up to 40 mg daily. Children aged 1–16 with GERD receive 0.5–1 mg/kg daily, divided into 2 doses, up to 40 mg twice daily; infants under 1 year use 0.5 mg/kg daily for up to 8 weeks.

Dose Adjustment in Specific Conditions

In moderate to severe renal impairment (creatinine clearance below 50 mL/min), doses are reduced by half (e.g., 20 mg daily) or intervals extended to 36–48 hours to prevent accumulation. Mild liver dysfunction allows standard dosing, with caution in severe cases due to minor metabolism. Elderly patients or those with mild symptoms may start at 10 mg daily, adjusted by response. Intravenous dosing mirrors oral regimens for acute needs, transitioning to oral as soon as possible.

Side Effects

Pepcid may cause a variety of side effects, though many patients experience only mild reactions with short-term use. Common issues include headache, dizziness, or constipation, often resolving without intervention. Diarrhea, nausea, or fatigue are also reported, typically transient as the body adjusts.

Less frequent effects include rash, dry mouth, or muscle pain, linked to systemic exposure. Rare but serious reactions, such as agranulocytosis, thrombocytopenia, or cardiac arrhythmias, require immediate cessation and medical attention, particularly with prolonged use or intravenous administration. Confusion or agitation may occur in sensitive individuals. Monitoring helps distinguish drug-related effects from underlying conditions.

Overdose

Symptoms of Overdose

Excessive intake of Pepcid is unlikely to cause acute toxicity due to its wide therapeutic index, with symptoms limited to amplified side effects like drowsiness, confusion, or gastrointestinal upset. Doses up to 800 mg daily have shown no consistent severe pattern, reflecting rapid clearance.

First Aid Measures

In case of overdose, medical consultation is advised, though emergency measures are rarely needed. No specific antidote exists, so treatment focuses on supportive care, such as hydration for diarrhea or rest for fatigue. Monitoring is recommended until symptoms subside, typically within 12–24 hours, given the drug’s half-life.

Drug Interactions

Effects on Other Medications

Pepcid minimally affects cytochrome P450 enzymes, reducing interactions with drugs like warfarin or theophylline. It may decrease absorption of pH-dependent drugs (e.g., ketoconazole) by raising gastric pH, potentially lowering efficacy, requiring spacing by 1–2 hours. Co-use with antacids may reduce bioavailability if taken simultaneously, though this is uncommon.

Drugs like probenecid may prolong famotidine elimination by competing for renal secretion, though this is rarely significant. Patients should report all medications to their healthcare provider to manage these minor interactions, especially in chronic use.

Compatibility with Alcohol and Food

Moderate alcohol use does not directly impair efficacy but may worsen acid-related symptoms, suggesting limited intake during therapy. Food does not significantly affect absorption, allowing administration with or without meals, though nighttime dosing without food enhances acid control.

Special Precautions

Use During Pregnancy and Breastfeeding

Pepcid is Category B in pregnancy, with no clear fetal harm in limited data, used cautiously if benefits outweigh risks, typically for severe GERD. It passes into breast milk in small amounts, so short-term use is generally safe with monitoring for infant effects, guided by medical advice.

Women of childbearing age should confirm non-pregnant status before starting and discuss risks with their provider during therapy planning.

Impact on Driving and Operating Machinery

The medication may cause dizziness or drowsiness in some patients, suggesting caution with driving or machinery until tolerance is clear. Most individuals resume normal activities once adjusted, but initial use warrants observation for these effects, typically resolving within hours.

Considerations for Elderly and Pediatric Populations

Elderly patients tolerate Pepcid well, with renal function monitoring key due to age-related decline, possibly requiring dose adjustment. Children over 1 year can use weight-adjusted dosing safely, while infants under 1 require careful medical supervision, with neonates excluded from intravenous use.