Ranitidine hydrochloride
Ranitidine hydrochloride (Zantac)
Ranitidine hydrochloride
(rah- NIH-tih-deen)
Pregnancy Category: B Alti-Ranitidine HCl Apo-Ranitidine Gen-Ranitidine Novo-Ranidine Nu-Ranit Zantac Zantac-C Zantac Efferdose Zantac GELdose Capsules (Rx) Zantac 75 (OTC)

Classification: H ₂ receptor antagonist

See Also: See also Histamine H ₂ Antagonists .

Action/Kinetics: Competitively inhibits gastric acid secretion by blocking the effect of histamine on histamine H ₂ receptors. Both daytime and nocturnal basal gastric acid secretion, as well as food- and pentagastrin-stimulated gastric acid are inhibited. Weak inhibitor of cytochrome P-450 (drug-metabolizing enzymes); thus, drug interactions involving inhibition of hepatic metabolism are not expected to occur. Food increases the bioavailability. Peak effect: PO, 1-3 hr; IM, IV, 15 min. t 1/2: 2.5-3 hr. Duration, nocturnal: 13 hr; basal: 4 hr. Serum level to inhibit 50% stimulated gastric acid secretion: 36-94 ng/mL. From 30% to 35% of a PO dose and from 68% to 79% of an IV dose excreted unchanged in urine.

Uses: Short-term (4-8 weeks) and maintenance treatment of duodenal ulcer. Pathologic hypersecretory conditions such as Zollinger-Ellison syndrome and systemic mastocytosis. Short-term treatment of active, benign gastric ulcers. Maintenance of healing of gastric ulcers. Gastroesophageal reflux disease, including erosive esophagitis. Maintenance of healing of erosive esophagitis. Investigational: Prophylaxis of pulmonary aspiration of acid during anesthesia, prevent gastric damage from NSAIDs, prevent stress ulcers, prevent acute upper GI bleeding, as part of multidrug regimen to eradicate Helicobacter pylori.

Contraindications: Cirrhosis of the liver, impaired renal or hepatic function.

Special Concerns: Use with caution during lactation and in clients with decreased hepatic or renal function. Safety and efficacy not established in children.

Side Effects: GI: Constipation, N&V;, diarrhea, abdominal pain, pancreatitis (rare). CNS: Headache, dizziness, malaise, insomnia, vertigo, confusion, anxiety, agitation, depression, fatigue, somnolence, hallucinations. CV: Bradycardia or tachycardia, premature ventricular beats following rapid IV use (especially in clients predisposed to cardiac rhythm disturbances), cardiac arrest. Hematologic: Thrombocytopenia, granulocytopenia, leukopenia, pancytopenia (sometimes with marrow hypoplasia), agranulocytosis, autoimmune hemolytic or aplastic anemia. Hepatic: Hepatotoxicity, jaundice, hepatitis, increase in ALT. Dermatologic: Erythema multiforme, rash, alopecia. Allergic: Bronchospasm, anaphylaxis angioneurotic edema (rare), rashes, fever, eosinophilia. Other: Arthralgia, gynecomastia, impotence, loss of libido, blurred vision, pain at injection site, local burning or itching following IV use.

Laboratory Test Alterations: False + test for urine protein using Multistix.

Drug Interactions: Antacids / May ranitidine absorption Diazepam / Diazepam effects R/T GI tract absorption Glipizide / Glipizide effects Procainamide / Procainamide excretion possible effect Theophylline / Possible theophylline pharmacologic and toxicologic effects Warfarin / May warfarin hypoprothrombinemic effects

How Supplied: Capsule: 150 mg, 300 mg; Granule for reconstitution: 150 mg; Injection: 1 mg/mL, 25 mg/mL; Syrup: 15 mg/mL; Tablet: 75 mg, 150 mg, 300 mg; Tablet, effervescent: 150 mg

Dosage
?Capsules (Soft Gelatin), Effervescent Tablets and Granules, Syrup, Tablets Duodenal ulcer, short-term.
Adults: 150 mg b.i.d. or 300 mg at bedtime to heal ulcer, although 100 mg b.i.d. will inhibit acid secretion and may be as effective as the higher dose. Maintenance: 150 mg at bedtime.
Pathologic hypersecretory conditions.
Adults: 150 mg b.i.d. (up to 6 g/day has been used in severe cases).
Benign gastric ulcer.
Adults: 150 mg b.i.d. for active ulcer. Maintenance: 150 mg at bedtime
Gastroesophageal reflux disease.
Adults: 150 mg b.i.d.
Erosive esophagitis.
Adults: 150 mg q.i.d.
Maintenenace of healing of erosive esophagitis.
Adults: 150 mg b.i.d.
?IM, IV Treatment and maintenance for duodenal ulcer, hypersecretory conditions, gastroesophageal reflux.
Adults, IM: 50 mg q 6-8 hr. Intermittent IV injection or infusion: 50 mg q 6-8 hr, not to exceed 400 mg/day. Continuous IV infusion: 6.25 mg/hr.
Zollinger-Ellison clients.
Continuous IV infusion: Dilute ranitidine in D5W to a concentration no greater than 2.5 mg/mL with an initial infusion rate of 1 mg/kg/hr. If after 4 hr the client shows a gastric acid output of greater than 10 mEq/hr or if symptoms appear, increase the dose by 0.5-mg/kg/hr increments and measure the acid output. Doses up to 2.5 mg/kg/hr may be necessary.