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Can I take 400 mg of cimetidine?

In the pharmaceutical industry, Cimetidine 400 mg is a standard therapeutic dose for an -receptor antagonist. As a pharmacist and manufacturer, I classify this as a “moderate-strength” dose, commonly used for the treatment of active gastric ulcers and Gastroesophageal Reflux Disease (GERD).

At your WHO-GMP facility in Mumbai, you likely manufacture this in 200 mg, 400 mg, and 800 mg strengths. While 400 mg is a common dose, its safety depends entirely on the condition being treated and the patient’s existing medication profile.

Standard Dosing Protocols

Condition Typical 400 mg Regimen Clinical Goal
Active Duodenal Ulcer 400 mg twice daily (or 800 mg at bedtime) Promotes healing of the mucosal lining.
GERD (Heartburn) 400 mg four times daily Provides 24-hour acid suppression.
Ulcer Prevention 400 mg once daily (at bedtime) Maintenance therapy to prevent recurrence.

 

The Pharmacist’s “Interaction Warning”

As a manufacturer, it is vital to highlight Cimetidine’s unique profile on your digital platforms. Unlike newer blockers (like Famotidine), Cimetidine is a potent inhibitor of the Cytochrome P450 (CYP450) enzyme system in the liver.

  • The Risk: Because it slows down liver enzymes, it can cause other drugs to build up to toxic levels in the blood.

  • What to Avoid: If the patient is taking Warfarin (blood thinner), Theophylline (asthma), or Phenytoin (epilepsy), a 400 mg dose of Cimetidine can be dangerous without medical supervision.

Mechanism of Action: Competitive H2 Blockade

Cimetidine works by specifically targeting the acid-producing cells in the stomach lining.

Selective Antagonism: It competitively inhibits histamine at the receptors of the gastric parietal cells.

Acid Reduction: This blockade reduces both the volume of gastric juice and its hydrogen ion (acid) concentration.

Healing Environment: By raising the pH of the stomach, it allows the damaged tissue (the ulcer) to heal without being constantly irritated by digestive acid.

The Manufacturer’s Perspective: Technical & Export

From a production and B2B standpoint at your facility in Mumbai, Cimetidine remains a strategic product for specific global markets:

  • The “Cost-Effective” USP: While PPIs (like Pantoprazole) are popular, Cimetidine is highly affordable. On your marketplace, position it as the ideal choice for government tenders and essential medicine lists in emerging markets.

  • Stability & Bioavailability: Cimetidine is relatively stable but sensitive to moisture. At our facility, we utilize Alu-Alu blister packaging to ensure a 36-month shelf life, which is essential for export to Zone IVb tropical regions (Africa/SE Asia).

  • Dossier Readiness: We provide full CTD/eCTD Dossiers to support your firm’s registration in international markets, ensuring your brand stands out for its technical and regulatory compliance.

Cimetidine Tablets