Cimetidine Dosage

Medically reviewed by Drugs.com. Last updated on May 29, 2023.

Usual Adult Dose for Duodenal Ulcer

800 to 1600 mg orally once a day at bedtime

• Duration of therapy: Up to 6 weeks

Comments:

• Most patients heal within 4 weeks; there are no safety data for the treatment of uncomplicated duodenal ulcer beyond 8 weeks.
• Treatment should be continued for 4 to 6 weeks unless healing has been demonstrated by endoscopic examination.
• Patients may use antacids to treat pain; however, the simultaneous use of antacids is not recommended, as antacids may interfere with the absorption of this drug.

Use: Short-term treatment of active duodenal ulcer

Usual Adult Dose for Duodenal Ulcer Prophylaxis

400 mg orally once a day at bedtime

• Duration of therapy: Up to 5 years

Use: Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer

Usual Adult Dose for Gastric Ulcer

800 mg orally once a day at bedtime OR 300 mg orally 4 times a day (with meals and at bedtime)

• Duration of therapy: 8 weeks

Comments:

• There are no data for the usefulness of treatment periods in patients with active benign gastric ulcers beyond 8 weeks.
• The once a day regimen is preferred for most patients due to convenience and a lower potential for drug interactions.
• Patients should be monitored during treatment to assure rapid progress to complete healing.

Use: Short-term treatment of active benign gastric ulcer

Usual Adult Dose for Zollinger-Ellison Syndrome

300 mg orally 4 times a day (with meals and at bedtime)

• Maximum dose: 2400 mg/day

Comments:

• Most patients receiving oral formulations heal within 4 weeks; there are no safety data for the treatment of uncomplicated duodenal ulcer beyond 8 weeks.
• Patients may use antacids to treat pain; however, the simultaneous use of antacids is not recommended, as antacids may interfere with the absorption of this drug.

Use: Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)

Usual Adult Dose for Erosive Esophagitis

800 mg orally 2 times a day OR 400 mg orally 4 times a day

• Duration of therapy: 12 weeks

Comments:

• Treatment periods beyond 12 weeks have not been established.
• Treatment is indicated to heal lesions and control symptoms.

Uses:

• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive gastroesophageal reflux disease (GERD)

Usual Adult Dose for Gastroesophageal Reflux Disease

800 mg orally 2 times a day OR 400 mg orally 4 times a day

• Duration of therapy: 12 weeks

Comments:

• Treatment periods beyond 12 weeks have not been established.
• Treatment is indicated to heal lesions and control symptoms.

Uses:

• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive gastroesophageal reflux disease (GERD)

Usual Adult Dose for Dyspepsia

OVER-THE-COUNTER (OTC) FORMULATIONS:

• Symptom relief: 200 mg orally with a glass of water
• Symptom prevention: 200 mg orally with a glass of water up to 30 minutes before consuming foods/beverages that cause heartburn
• Maximum dose: 2 tablets/day
• Duration of therapy: Up to 14 days (self-treatment)

Uses:

• Relieves heartburn associated with acid indigestion and sour stomach
• Prevents heartburn associated with acid indigestion and sour stomach brought on by eating/drinking certain foods and beverages

Usual Pediatric Dose for Duodenal Ulcer

Pediatric Patients:

• Use is not recommended unless the anticipated benefits outweigh the potential risk.
• The manufacturer states, "In very limited experience, doses of 20 to 40 mg/kg per day have been used."

Uses:

• Short-term treatment of active duodenal ulcer
• Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer
• Short-term treatment of active benign gastric ulcer
• Prevention of upper gastrointestinal bleeding in critically ill patients
• Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)
• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive GERD

Usual Pediatric Dose for Duodenal Ulcer Prophylaxis

Pediatric Patients:

• Use is not recommended unless the anticipated benefits outweigh the potential risk.
• The manufacturer states, "In very limited experience, doses of 20 to 40 mg/kg per day have been used."

Uses:

• Short-term treatment of active duodenal ulcer
• Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer
• Short-term treatment of active benign gastric ulcer
• Prevention of upper gastrointestinal bleeding in critically ill patients
• Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)
• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive GERD

Usual Pediatric Dose for Erosive Esophagitis

Pediatric Patients:

• Use is not recommended unless the anticipated benefits outweigh the potential risk.
• The manufacturer states, "In very limited experience, doses of 20 to 40 mg/kg per day have been used."

Uses:

• Short-term treatment of active duodenal ulcer
• Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer
• Short-term treatment of active benign gastric ulcer
• Prevention of upper gastrointestinal bleeding in critically ill patients
• Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)
• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive GERD

Usual Pediatric Dose for Gastric Ulcer

Pediatric Patients:

• Use is not recommended unless the anticipated benefits outweigh the potential risk.
• The manufacturer states, "In very limited experience, doses of 20 to 40 mg/kg per day have been used."

Uses:

• Short-term treatment of active duodenal ulcer
• Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer
• Short-term treatment of active benign gastric ulcer
• Prevention of upper gastrointestinal bleeding in critically ill patients
• Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)
• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive GERD

Usual Pediatric Dose for Gastroesophageal Reflux Disease

Pediatric Patients:

• Use is not recommended unless the anticipated benefits outweigh the potential risk.
• The manufacturer states, "In very limited experience, doses of 20 to 40 mg/kg per day have been used."

Uses:

• Short-term treatment of active duodenal ulcer
• Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer
• Short-term treatment of active benign gastric ulcer
• Prevention of upper gastrointestinal bleeding in critically ill patients
• Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)
• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive GERD

Usual Pediatric Dose for Stress Ulcer Prophylaxis

Pediatric Patients:

• Use is not recommended unless the anticipated benefits outweigh the potential risk.
• The manufacturer states, "In very limited experience, doses of 20 to 40 mg/kg per day have been used."

Uses:

• Short-term treatment of active duodenal ulcer
• Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer
• Short-term treatment of active benign gastric ulcer
• Prevention of upper gastrointestinal bleeding in critically ill patients
• Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)
• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive GERD

Usual Pediatric Dose for Zollinger-Ellison Syndrome

Pediatric Patients:

• Use is not recommended unless the anticipated benefits outweigh the potential risk.
• The manufacturer states, "In very limited experience, doses of 20 to 40 mg/kg per day have been used."

Uses:

• Short-term treatment of active duodenal ulcer
• Maintenance therapy for duodenal ulcer patients at reduced dosage after healing of active ulcer
• Short-term treatment of active benign gastric ulcer
• Prevention of upper gastrointestinal bleeding in critically ill patients
• Treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, systemic mastocytosis, multiple endocrine adenomas)
• Treatment of erosive esophagitis diagnosed by endoscopy
• Treatment of erosive GERD

Usual Pediatric Dose for Dyspepsia

12 years and older:
OTC FORMULATIONS:

• Symptom relief: 200 mg orally with a glass of water
• Symptom prevention: 200 mg orally with a glass of water up to 30 minutes before consuming foods/beverages that cause heartburn
• Maximum dose: 2 tablets/day
• Duration of therapy: Up to 14 days (self-treatment)

Uses:

• Relieves heartburn associated with acid indigestion and sour stomach
• Prevents heartburn associated with acid indigestion and sour stomach brought on by eating/drinking certain foods and beverages

Renal Dose Adjustments

Severe renal dysfunction: 300 mg orally every 12 hours

Comment: The frequency may be increased to every 8 hours (or even further) with caution if the patient's condition requires.

Severe renal failure: The lowest frequency of dosing compatible with adequate patient response should be used.

Liver Dose Adjustments

Liver dysfunction with renal dysfunction: Dose adjustment(s) may be required; however, no specific guidelines have been suggested. Caution recommended.

Dose Adjustments

Therapeutic drug monitoring/range: Intragastric secretory rate or 10 mEq/hour or less

Patients with endoscopically demonstrated ulcers larger than 1 cm AND are heavy smokers (e.g., smoke 1 or more pack of cigarettes/day): Consider 1600 mg orally once a day at bedtime for 4 weeks OR 800 mg orally once a day for 8 weeks.

Precautions

CONTRAINDICATIONS:

• Hypersensitivity to the active component, other acid reducers, or any of the ingredients

Safety and efficacy of OTC formulations have not been established in patients younger than 12 years.
Safety and efficacy of prescription formulations have not been established in patients younger than 16 years.

Consult WARNINGS section for additional precautions.

Dialysis

Hemodialysis: The dose should be given at the end of the hemodialysis session.
Peritoneal dialysis: Data not available

Other Comments

Administration advice:

• Tablets should be swallowed with water.
• Malignancy should be excluded by endoscopy and biopsy prior to treatment in patients with gastric ulceration.

Storage requirements:

• Protect from light.

General:

• Clinical trials of prolonged, continuous treatment have not revealed adverse reactions related to long-term treatment; however, patients receiving prolonged treatment should be periodically assessed for safety.

Monitoring:

• HEMATOLOGIC: Prothrombin time in patients taking coumarins concomitantly

Patient advice:

• Inform patients that this drug may cause dizziness or drowsiness, and they should avoid driving or operating machinery if these side effects occur.
• Patients should be advised that symptomatic response to treatment does not preclude the presence of a gastric malignancy.
• Advise patients to speak to their healthcare provider if they become pregnant, intend to become pregnant, or are breastfeeding.

Frequently asked questions

• Can OTC wart medicine help stop molluscum contagiosum?

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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