Metamizol Zentiva (Metamizole Sodium Monohydrate)

Metamizol Zentiva belongs to the pyrazolone class and is used for conditions requiring analgesic or antipyretic therapy.

• Pain: provides relief of moderate to severe acute or chronic pain.
• Fever: lowers elevated body temperature in febrile states.
• Post‑operative pain: helps control pain following surgical procedures.

• Metamizole sodium inhibits cyclooxygenase activity, leading to reduced prostaglandin synthesis. This diminishes the peripheral sensitisation of nociceptors and lowers the hypothalamic set‑point for temperature regulation, producing analgesic and antipyretic effects. The exact molecular pathways are not fully elucidated, but the drug’s action is primarily mediated through prostaglandin inhibition.

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

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Dizziness: transient light‑headedness.
• Skin rash: mild erythema or itching.

Serious or Rare Side Effects

• Agranulocytosis: severe reduction in white blood cells.
• Aplastic anemia: bone‑marrow failure leading to pancytopenia.
• Severe skin reactions: Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Hepatic injury: elevated liver enzymes or hepatitis.
• Anaphylaxis: acute allergic reaction with airway compromise.

Before initiating therapy with Metamizol Zentiva, consider the following safety measures.

• Blood count monitoring: assess baseline and periodic leukocyte levels.
• Infection vigilance: watch for signs of infection due to possible neutropenia.
• Renal/hepatic impairment: use cautiously and adjust if organ function is compromised.
• Hypersensitivity: avoid in patients with known allergy to pyrazolones.
• Pediatric use: restrict to cases where benefits outweigh risks and under specialist guidance.
• Store at room temperature: keep in the original packaging, protect from moisture and direct sunlight.

Metamizol Zentiva can affect the activity of several other medicines.

Major Interactions (Avoid)

• Anticoagulants (e.g., warfarin): increased risk of bleeding.
• Other NSAIDs or analgesics: additive gastrointestinal and renal toxicity.
• Drugs causing bone‑marrow suppression (e.g., chemotherapy agents): heightened risk of agranulocytosis.

Moderate Interactions (Monitor Closely)

• ACE inhibitors or ARBs: possible enhancement of hypotensive effects.
• Lithium: may increase serum lithium concentrations.
• Methotrexate: potential for increased toxicity.
• Diuretics: may potentiate electrolyte disturbances.