Metamizol Medreg (Metamizole Sodium Monohydrate)

Metamizole is an analgesic and antipyretic that acts on pain and fever pathways.

• Pain: provides effective relief of moderate to severe acute pain.
• Fever: lowers elevated body temperature when other antipyretics are insufficient.
• Post‑operative pain: helps manage pain following surgical procedures.
• Visceral colic pain: alleviates painful spasms of the gastrointestinal tract.

• Metamizole inhibits cyclooxygenase activity, leading to reduced synthesis of prostaglandins that mediate pain and fever. While the precise mechanism is not fully defined, the drug’s effect on prostaglandin pathways contributes to its analgesic and antipyretic properties without the typical NSAID‑related gastric irritation.

Metamizole may cause a range of adverse reactions, from mild to severe.

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Vomiting: occasional episodes after dosing.
• Dizziness: transient light‑headedness.
• Hypotension: occasional drop in blood pressure.
• Skin rash: mild erythema or itching.
• Leukopenia: mild reduction in white blood cells.

Serious or Rare Side Effects

• Agranulocytosis: severe depletion of neutrophils, potentially life‑threatening.
• Severe allergic reactions: including anaphylaxis.
• Stevens‑Johnson syndrome: rare severe skin reaction.
• Hepatotoxicity: liver enzyme elevations or injury.
• Renal impairment: acute kidney injury in susceptible individuals.
• Blood dyscrasias: rare hematologic abnormalities.

Metamizole should be used under medical supervision with attention to specific safety considerations.

• Medical supervision: prescribe and monitor therapy according to clinical guidelines.
• Blood count monitoring: regularly assess white blood cell levels to detect agranulocytosis early.
• Hypersensitivity: avoid in patients with known allergy to pyrazolones.
• Renal/hepatic impairment: use caution and adjust dosing if organ dysfunction is present.
• Pregnancy: avoid unless benefits outweigh uncertain risks, as safety data are limited.
• Store at ambient temperature: keep in the original packaging, protect from moisture and direct sunlight.

Metamizole can interact with other medicines, requiring attention to potential additive effects.

Major Interactions (Avoid)

• Concurrent myelosuppressive agents: may increase risk of severe blood cell suppression.
• Other pyrazolones or similar analgesics: heightened risk of agranulocytosis.
• Anticoagulants (e.g., warfarin): may enhance bleeding tendency.

Moderate Interactions (Monitor Closely)

• Antihypertensives: additive hypotensive effect may require blood pressure monitoring.
• Alcohol: combined use can increase dizziness and gastrointestinal irritation.
• CYP450 substrates: may alter metabolism of certain drugs, necessitating dose adjustments.