Famotidine Injection

• Type: Acid-reducing medication

• Drug Class: H2-receptor antagonist (H2 blocker)

• Form: Sterile solution for intravenous (IV) or intramuscular (IM) administration

How It Works

• Famotidine selectively blocks histamine H2 receptors in the stomach lining.

• This leads to reduced gastric acid secretion (both basal and stimulated), lowering stomach acidity and allowing ulcers or erosions to heal.

Common Uses

Famotidine injection is generally used when oral therapy is not possible, such as in:

• Peptic ulcers (stomach and duodenal ulcers)

• Gastroesophageal reflux disease (GERD) with severe symptoms

• Zollinger–Ellison syndrome (excess stomach acid due to gastrin-secreting tumor)

• Stress ulcer prophylaxis in critically ill or ICU patients

• Upper GI bleeding (as part of supportive management)

• Perioperative acid suppression to prevent aspiration pneumonitis

Advantages

• Rapid onset of action (IV form starts working within minutes)

• Useful for patients unable to take oral medications

• Generally well tolerated compared to proton pump inhibitors (PPIs)

• Can be given intermittently or as a continuous IV infusion in severe acid hypersecretion

Possible Side Effects

Common:

• Headache

• Dizziness

• Injection site pain

Less Common:

• Constipation or diarrhea

• Fatigue

• Rare allergic reactions

Very Rare (High Doses/Prolonged Use):

• Confusion or hallucinations (mainly in elderly or critically ill patients)

• Bradycardia or hypotension (if given too rapidly IV)

Precautions

• Use with caution in patients with severe kidney impairment (dose adjustment needed)

• Not a substitute for ruling out gastric cancer in patients with unexplained weight loss or GI bleeding

• Should be injected slowly to avoid cardiovascular side effects

• Long-term use may mask symptoms of serious GI conditions