Cimetidine

Antipeptic Ulcerant · H2 blocker

Indications

Inj/Tab: For the prophylaxis of stress ulcer syndrome: Duodenal ulcer, benign gastric ulcer, recurrent and stomal ulceration, reflux oesophagitis, Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas and other conditions where reduction of gastric acid secretion is likely to be beneficial. NSAID-associated ulceration, short-bowel syndrome, to reduce degradation of pancreatic enzyme supplements. Susp: Treatment of acute gastritis which can manifest as heartburn, epigastric pain, hyperacidity, dyspepsia or acute aggravation of chronic gastritis.

Dosage

TABLET: Adults: Active duodenal ulcer: Single dose of 800 mg at bed time or 400 mg at breakfast and 400 mg at bed time, or 200 mg three times a day with meals and 400 mg at bedtime. Reflux oesophagitis: 400 mg four times a day with meals and at bedtime for upto 12 wk is indicated. Zollinger-Ellison syndrome and other cases of high gastric secretion: 200 mg 3 times a day with meals and 400 mg at bedtime. Acid related dyspepsia: 200 mg 4 times a day (with meals and at bed time). In haemorrhage from ulceration or erosion of upper Gl tract, stress ulcers: 200 mg three times daily with meals and 400 mg at bedtime. In non- ulcer acid related conditions: 200 mg 4 times a day (with meals and at bed time). NSAID-associated ulceration: 400 mg two times daily for 8 wks, taken with breakfast and at night, or 800 mg daily for 8 wks taken at night, if required increase dose to 400 mg four times…

Administration

IV: May be administered as a slow IV push or preferably as an IV intermittent or IV continuous infusion. Administer each 300 mg (or fraction thereof) over a minimum of 5 min when giving IV push. Give intermittent infusion over 15-30 min for each 300 mg dose. Intermittent infusions are administered over 15-30 min at a final concentration not to exceed 6 mg/mL; for patients with an active bleed, preferred method of administration is continuous infusion. Compatibility: Stable in D5LR, D5 ¼ NS, D5 ½ NS, D5W, LR, sodium bicarbonate 5%. Y-site administration: Drug to Drug IV Compatibility: Acyclovir, aztreonam, cisatracurium, dexamethasone, digoxin, diltiazem, diphenhydramine, dobutamine, enalapril, epinephrine, esmolol, fentanyl, fluconazole, furosemide, heparin, hydromorphone, labetalol, levofloxacin, linezolid, lorazepam, meropenem, methylprednisolone, metoprolol, metronidazole, midazolam,…

Adverse Effects

Diarrhoea, dizziness, rash, tiredness. Gynaecomastia, occasional reversible liver damage, confusion. Very rarely interstitial nephritis, acute pancreatitis, thrombocytopenia, leucopenia, pancytopenia, aplastic anaemia, fever, headache, myalgia, arthralgia, sinus bradycardia, tachycardia, heart block, anaphylaxis, hallucinations, depression, reversible impotence.

Risk Factor (Pregnancy/Lactation)

Pregnancy: No evidence of risk in humans. Lactation: Contraindicated or not recommended. Precautions: Exclude malignant disease before and during treatment. Impaired renal function. Monitor patients on long term therapy.

Interactions

Oral anticoagulants, phenytoin, theophylline, IV lignocaine.

Advice to Patient

Take with meals. Contact prescriber if there is constant diarrhoea, dark stools, coffee ground-like vomit, dizziness, confusion, agitation, rash, unusual bleeding or bruising, fever or sore throat. Do not take antacids within 1 hour of taking cimetidine. Reduce intake of xanthine-containing foods and beverages which may decrease iron absorption. Avoid alcohol and smoking during therapy.

Pharmacokinetics

Onset: Oral: 30 mins. Duration: 4-8 hrs. Absorption: Rapid (60%-70%). Metabolism: Hepatic. Bioavailability: 50%-60%. Half-life elimination: 2 hrs. Time to peak, serum: Oral: 1-3 hrs. Excretion: Urine (approx. 90%). Faeces (10%).

Brands with this active ingredient

Compiled by Healify Pharmacy from published drug references. How we compile it →

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