What is the active compound in Losec (omeprazole) 20mg?

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The Active Compound in Losec 20mg

The active compound in Losec 20mg is omeprazole, a substituted benzimidazole with the chemical formula C17H19N3O3S and molecular weight of 345.42 g/mol. 1

Chemical Structure and Properties

Omeprazole is a proton pump inhibitor (PPI) with the chemical name 5-methoxy-2[[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]sulfinyl]-1H-benzimidazole. It has the following properties:

  • White to off-white crystalline powder
  • Melts with decomposition at approximately 155°C
  • Weak base that is freely soluble in ethanol and methanol
  • Slightly soluble in acetone and isopropanol
  • Very slightly soluble in water
  • Stability is pH-dependent (rapidly degraded in acid media but stable under alkaline conditions) 1

Formulation Details

In Losec 20mg capsules, the active compound omeprazole is present in the form of enteric-coated granules. This enteric coating is essential because:

  • It protects omeprazole from degradation by stomach acid
  • Ensures the drug reaches the small intestine intact where it can be absorbed
  • Maintains the drug's stability and efficacy 1

Mechanism of Action

Omeprazole functions as a gastric acid pump inhibitor that:

  • Controls gastric acid secretion at the final stage of the acid secretory pathway
  • Irreversibly blocks the proton pump (H+/K+ ATPase) in gastric parietal cells
  • Reduces both basal and stimulated acid secretion regardless of the stimulus
  • Is 2-10 times more potent than cimetidine (an H2-receptor antagonist) in inhibiting gastric acid secretion 2

Pharmacological Classification

Omeprazole belongs to the class of drugs known as proton pump inhibitors (PPIs), which are the most potent inhibitors of gastric acid secretion available. Unlike H2-receptor antagonists that block one pathway of acid secretion, PPIs block the final common pathway of acid production, making them more effective for acid suppression. 3

This information provides a comprehensive understanding of the active compound in Losec 20mg, its chemical properties, and its mechanism of action in treating acid-related disorders.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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