Famotidine Pharmacology

Famotidine

About Famotidine
Guanidine:Thiazole derivative,a histamine H2-receptor antagonist, Anti-secretory,Antiulcer.
Mechanism of Action of Famotidine
Famotidine is a H2 (Histamine) receptor antagonist. Histamine is the most potent stimulus of acid secretion and acts as the common mediator. H2 receptor is a G-protein coupled receptor. It induces adenylate cyclase which converts ATP to cyclic AMP. This cyclic AMP acts on proton pump and exchange extracellular potassium ion for intracellular hydrogen ion across the parietal cell membrane. Famotidine reversibly competes with Histamine for binding to H2 receptors on the parietal cells and predominantly inhibits basal acid secretion.
Anaesthetic adjuncts: It is used in patients undergoing prolonged operations, caesarian section; obese patients are at increased risk of gastric regurgitation and aspiration pneumonia. It raises pH of gastric juice and also reduces its volume and thus chances of regurgitation. It is now routinely used before prolonged surgery.
Pharmacokinets of Famotidine
Absorption: Famotidine is 40 - 45 % absorbed after oral administration. Distribution: Distributed mainly in unbound form. Metabolism: Famotidine undergoes metabolism in the liver. Excretion: It is excreted mainly in urine and in the faeces.
Onset of Action for Famotidine
60 minutes
Duration of Action for Famotidine
2.5-3.5 hours
Half Life of Famotidine
2.5 - 3.5 hours
Side Effects of Famotidine
1.Headache
2.Dizziness
3.Constipation
4.Diarrhoea
5.Nausea
6.Vertigo
7.Confusion
8.Rash
9.Thrombocytopenia
10.Leukopenia
Contra-indications of Famotidine
1. Hypersensitivity to Famotidine
Special Precautions while taking Famotidine
1.Hepatic impairment
2.Renal impairment
3.Acute Porphyria
Pregnancy Related Information
Use with caution.
Old Age Related Information
Use with caution.
Breast Feeding Related Information
Use with caution.
Children Related Information
Use with caution.
NEONATES: contraindicated
Indications for Famotidine
1.Duodenal ulcer
2.Benign gastric ulcer
3.Zollinger- Ellison syndrome
4.Gastroesophageal reflux diseases
5.Acid indigestion
6.Heart burn
7.Sour stomach
8.Preanaesthetic medication (PAM)
Interactions for Famotidine
Antacids: Bioavailability of Famotidine slightly decreased, hence antacids in small doses can be given concomitantly.
Typical Dosage for Famotidine
Adult: 40mg / day
Duodenal ulcer, benign gastric ulcer: 40 mg /day as single dose at bed time or in 2 divided dose (morning and bed time) for 1 - 2 months. Maintenance dose: 20 mg / day at bed time.
Zollinger- Ellison syndrome: 80mg / day in 4 divided doses; dose can be increased if necessary to a maximum up to 800 mg / day
Gastroesophageal reflux disease: 40 mg / day as single dose at bed time or in 2 divided doses (morning and bed time) for maximum 2-3 months, dose can be increased to 80 mg / day in 2 divided doses if needed.
Acid indigestion, Heart burn, Sour stomach: Dose: 20mg/day in 2 divided doses.
PAM: 20mg given night before and in the morning before surgical procedure.
Schedule of Famotidine
H
Storage Requirements for Famotidine
Store at 15 - 30 degree C in a tightly closed container. Protect from light.
Effects of Missed Dosage of Famotidine
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Famotidine
Give supportive measures and symptomatic treatment. Drug can be removed from the body by inducing emesis and or by gastric lavage. Activated charcoal is given to reduce the absorption of the drug. Haemodialysis can be done if necessary.

Home Delivery for Famotidine in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including famotidine.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for famotidine and other medicines and health products. Home delivery services for famotidine may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take famotidine only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for famotidine before they complete the sale. You can get this information while placing the order for famotidine with the pharmacy.

Famotidine is a generic medicine name and there are several brands available for it. Some of the brands for famotidine might be better known than famotidine itself. If the pharmacy that's willing to deliver medicines to your home doesn't have famotidine in stock, you can ask for one of the branded alternatives for famotidine.