Famotidine | H₂ Antagonist | CAS 76824-35-6 | API
Product Name: Famotidine
CAS No.: 76824-35-6
Molecular Formula: C₈H₁₅N₇O₂S₃
Appearance: White or almost white crystalline powder
Solubility: Practically insoluble in water; sparingly soluble in methanol; very slightly soluble in ethanol. Water-soluble salts are used for parenteral administration.
Stability: Stable under recommended storage conditions
1. Introduction
Famotidine is a potent and highly selective H₂ histamine receptor blocker used to reduce gastric acid production. It is used for the treatment and prevention of various acid-related diseases, including peptic ulcers, gastroesophageal reflux disease (GERD), and Zollinger-Ellison syndrome.
Famotidine is among the most effective drugs in the H₂ antagonist class, surpassing ranitidine and cimetidine in potency. Its high selectivity for H₂ receptors and favorable safety profile have made it a popular choice for long-term therapy of acid-related conditions. Famotidine suppresses both basal and stimulated gastric acid secretion.
2. Chemical Structure & Synthesis
Famotidine has a complex heterocyclic structure featuring a thiazole ring and a guanidine group.
Molecular Formula: C₈H₁₅N₇O₂S₃
The synthesis of famotidine is a complex multi-step process involving the construction of the thiazole ring followed by attachment of the side chain with sulfonamide and guanidine groups. Special attention is given to stereochemical control and purity of intermediates and the final compound.
3. Physicochemical Properties
| Property | Description |
|---|---|
| Appearance | White or almost white crystalline powder |
| Solubility | Practically insoluble in water; sparingly soluble in methanol; very slightly soluble in ethanol |
| Stability | Stable under recommended storage conditions |
| Pharmacokinetics | GI absorption incomplete and variable; minimal hepatic metabolism; primarily excreted unchanged via kidneys |
4. Applications
| Indication | Use |
|---|---|
| Peptic Ulcer Disease | Healing of gastric and duodenal ulcers; prevention of recurrence |
| GERD Therapy | Relief of heartburn symptoms; treatment of erosive esophagitis |
| Zollinger-Ellison Syndrome | Control of pathological gastric acid hypersecretion |
| Aspiration Pneumonitis Prophylaxis | Preoperative reduction of gastric acid volume and acidity |
5. Conclusion
Famotidine is an important drug for the treatment of acid-related gastrointestinal disorders. Its high efficacy, selectivity, and favorable safety profile make it a valuable tool in clinical practice. The drug continues to be widely used, particularly in situations requiring rapid and reliable suppression of acid production.
