Histamine receptor blockers inhibit gastric acid secretion, particularly effective against nocturnal acid secretion. They block histamine binding to H2 receptors competitively, leading to decreased intracellular signaling molecules for gastric acid release, in turn decreasing the secretion. Famotidine decreases stomach acid production.
Antacids are only employed for intercurrent pain relief and acidity and are self-prescribed by the patients. The antacids are used for providing symptomatic relief from Gastroesophageal reflux disease (GERD), acid eructation, and heartburn.
| Parameters | Details |
|---|---|
| Category of Drug | Histamine receptor blockers |
| Mechanism of Action | Famotidine decreases stomach acid production. |
| Indications | 1. Duodenal or benign gastric ulcers 2. GERD 3. Zollinger-Ellison syndrome |
| Structure |  |
| Molecular details | 1. Molecular Formula- C8H15N7O2S3 2. Molecular Weight- 373.9 g/mol |
| IUPAC Name | 3-[[2-(diaminomethylideneamino)-1,3-thiazol-4-yl]methylsulfanyl]-N‘-sulfamoylpropanimidamide;hydron;chloride |
| Well Known Pharmaceutical Brands | 1. FAMOCID- SUN 2. FAMTAC- ABBOTT 3. TOPCID- TORRENT PHARMA 4. FACID- INTAS 5. FAMONEXT- CADILA |
| Available dosage forms | 1. TABLETS 2. CAPSULES 3. INJECTION |
| Dose | 1. 40 mg orally once a day 2. 20 mg orally 2 times a day |
| Pharmacokinetic properties | 1. The oral bioavailability-40-50%, 2. Cmax -1-4 hours 3. Vd- 1.0 to 1.3 L/kg 4. The protein binding-15 to 22%. 5. elimination- 25-30% through hepatic metabolism. 6. metabolite- S-oxide 7. half-life -2 to 4 hours |
| Storage conditions | 1. Store protected from light, 2. Injection to be stored between 2-8⁰C |
| Contraindications | Hypersensitivity |
| Precautions | 1. Gastric malignancy 2. Impaired renal function 3. liver cirrhosis 4. Pregnancy 5. lactation |
| Adverse Effects | 1. Headache 2. dizziness 3. constipation 4. diarrhea 5. nausea 6.vomiting 7.anorexia 8. rash 9.fatigue 10.gynaecomastia 11. impotence |
| Pregnancy Category | B |
References
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