famotidine

Action and Spectrum

Actions and Spectrum 

The regulation of acid secretion has been affected in conditions like ulcers that are linked to acid hypersecretion. Famotidine inhibits the effects of histamine by acting on H2 receptors. 

Spectrum: 

Famotidine is used in treating a wide range of ulcers of the intestines and stomach. It also reduces symptoms like cough, heartburn, swallowing difficulties, and pain in the stomach. 

Drug Interaction

Adverse Reaction

Frequency Defined 

1-10% 

Constipation (1.2%) 

Diarrhea (1.7%) 

Headache (4.7%) 

Dizziness (1.3%) 

Frequency Not Defined 

Arrhythmia 

AV block 

Fever 

Fatigue 

Prolonged QT interval 

Asthenia 

Palpitation 

Black Box Warning

Black Box Warning 

To be used in caution with patients suffering from kidney diseases 

Contraindication / Caution

Contraindication/Caution 

Contraindication: 

Hypersensitivity 

Caution: 

Kidney failure 

Gastric malignancy 

Pregnancy / Lactation

Pregnancy/Lactation 

Pregnancy warnings: 

US FDA pregnancy category: Not assigned 

Lactation: 

Excreted into human milk is known 

Pregnancy Categories: 

Category A: Satisfactory and well-controlled studies show no risk to the fetus in the first or later trimester. 

Category B: No evidence shown of risk to the fetus found in animal reproduction studies, and there are not enough studies on pregnant women 

Category C: Adverse effects on the fetus found with evidence in animal reproduction studies and no adequate evidence for a result in humans must take care of potential risks in pregnant women 

Category D: adequate data available with sufficient evidence of human fetal risk from various platforms, but despite the potential risk, and used only in emergency cases for potential benefits. 

Category X: Drugs listed in this category outweigh the risks over benefits. Hence these categories of drugs need to be avoided by pregnant women. 

Category N: There is no data available for the drug under this category 

Pharmacology

Pharmacology 

It is a histamine H2 receptor antagonist. It leads to the reduction of acid generation thereby lowering the level of acid and pepsin which also decreases the quantity of gastric secretion. It has a suppressing effect in the basal and nocturnal gastric acid production. 

Pharmacodynamics: 

Famotidine acts by decreasing the acid secretion in the stomach which helps in relieving heartburn and indigestion that are mediated by acid. After oral administration of 5 to 40 mg it can achieve a dose-dependent mode of action resulting in suppression of both basal and stimulated gastric acid output. The 40-mg dosage reaches the maximum effect in 1 to 3 hours after taking the medication and remains active for 10 to 12 hours. 

Pharmacokinetics: 

Absorption 

Bioavailability is found to be 40 to 45% with a peak plasma time of 20 minutes when administered intravenously and 1h to 4h when administered orally. 

Distribution 

15 to 20% of the drug is known to be protein-bound 

Metabolism 

It undergoes hepatic metabolism with famotidine S-oxide as the inactive metabolite 

Elimination and excretion 

65-70% of the drug is eliminated through the renal route. 70% of it is eliminated in unchanged form through urine when administered intravenously 

Renal clearance- 250 to 450ml/min 

Half-life: 

2 hours to 4 hours 

Adminstartion

Administration 

It is administered orally in the form of tablets before meals 

Patient Information Leaflet

Patient Information Leaflet 

Generic Name: famotidine 

Why do we use famotidine? 

Famotidine belongs to the class of histamine-2 receptor antagonists which is utilized for various medical purposes: 

Gastric Acid Reduction: It reduces the gastric acid production and effectively treats peptic ulcer. It is used for the purpose of controlling conditions like acid reflux and ulcers because reducing the acidity levels in the stomach helps to calm the same down. 

Peptic Ulcer Treatment: It is one of the effective medicines to treat duodenal ulcer and gastric stases by decreasing the digestive acidic secretion and it protects from the injury as well as the relapse of peptic ulcer. 

Gastroesophageal Reflux Disease (GERD): It is used to treat GERD which is the condition of stomach acid regurgitation into the esophagus causing heartburn and regurgitation. 

Prevention of Stress Ulcers: Famotidine is typically used in the hospitalized patients as well as during procedures that can cause stress ulcers.