Description

Simple

A medication used to treat acid reflux, stomach ulcers, and indigestion.

Clinical

A histamine H2 receptor antagonist used to manage GERD, peptic ulcer disease, and indigestion.

Overview

A histamine congener, it competitively inhibits histamine binding to histamine H2 receptors. Cimetidine has a range of pharmacological actions. It inhibits gastric acid secretion, as well as pepsin and gastrins output. It also blocks the activity of cytochrome P-450 which might explain proposals for use in neoadjuvant therapy.

Pharmacology

Indication

For the treatment and the management of acid-reflux disorders (GERD), peptic ulcer disease, heartburn, and acid indigestion.

Pharmacodynamic

Cimetidine is a histamine H2-receptor antagonist. It reduces basal and nocturnal gastric acid secretion and a reduction in gastric volume, acidity, and amount of gastric acid released in response to stimuli including food, caffeine, insulin, betazole, or pentagastrin. It is used to treat... Read more

Mechanism of action

Cimetidine binds to an H2-receptor located on the basolateral membrane of the gastric parietal cell, blocking histamine effects. This competitive inhibition results in reduced gastric acid secretion and a reduction in gastric volume and acidity.

Absorption

Rapid 60-70%

Protein binding

15-20%

Volume of distribution

Information currently not available.

Clearance

Information currently not available.

Half life

2 hours

Route of elimination

The principal route of excretion of cimetidine is the urine.

Toxicity

Symptoms of overdose include nausea, vomiting, diarrhea, increased saliva production, difficulty breathing, and a fast heartbeat.

Adverse Effects

Effect Regions Age Groups Incidences Evidence Type
Gynecomastia US
  • Kind: experimental
    • Percent: 0.3-4%
  • Clinical Trial
    Headaches US
  • Kind: experimental
    • Percent: 2.1-3.5%
  • Clinical Trial
    Diarrhea US
  • Kind: experimental
    • Percent: 1%
  • Clinical Trial
    Decreased WBCs US
  • Kind: experimental
    • Percent: 0.001%
  • Clinical Trial
    Thrombocytopenia US
  • Kind: experimental
    • Percent: 0.0003%
  • Clinical Trial
    Agranulocytosis US
  • Kind: experimental
    • Percent: 0.0003%
  • Clinical Trial
    Strongyloidiasis hyperinfection US
    Clinical Trial
    Hypersensitivity Vasculitis US
    Clinical Trial
    Anaphylaxis US
    Clinical Trial
    Interstitial nephritis US
    Clinical Trial
    Increased serum creatinine US
    Clinical Trial
    Periportal hepatic fibrosis US
    Clinical Trial
    Cholestatic hepatocellular effects US
    Clinical Trial
    Allergic Reaction US
    Clinical Trial
    Fever US
    Clinical Trial
    Aplastic Anemia US
    Clinical Trial
    Pancytopenia US
    Clinical Trial
    Increased serum transaminases US
    Clinical Trial
    Immune hemolytic anemia US
    Clinical Trial
    Anxiety US
    Clinical Trial
    Depression US
    Clinical Trial
    Disorientation US
    Clinical Trial
    Hallucinations US
    Clinical Trial
    Alopecia US
    Clinical Trial
    Epidermal necrolysis US
    Clinical Trial
    Erythema multiforme US
    Clinical Trial
    Exfoliative dermatitis US
    Clinical Trial
    Generalized exfoliative erythroderma US
    Clinical Trial
    Arthralgia US
    Clinical Trial
    Polymyositis US
    Clinical Trial
    Rash US
    Clinical Trial
    Stevens-Johnson Syndrome US
    Clinical Trial
    Urinary Retention US
    Clinical Trial
    Bradycardia US
    Clinical Trial
    Tachycardia US
    Clinical Trial
    AV heart block US
    Clinical Trial
    Agitation US
    Clinical Trial
    Psychosis US
    Clinical Trial
    Mental confusion US
    Clinical Trial

    Contraindications

    Information currently not available.

    Food Interactions

    Avoid alcohol.

    Limit caffeine intake.

    Take with food.