Novalgina (Metamizole Sodium)

Novalgina (metamizole sodium) is used for pain and fever management in several clinical situations, acting as a potent systemic analgesic and antipyretic.

• Moderate to severe pain: provides rapid analgesia for acute or chronic painful conditions such as postoperative pain.
• High fever: reduces elevated body temperature when conventional antipyretics are insufficient.
• Post‑operative pain: offers effective relief during the immediate recovery period after surgery.
• Colic: alleviates visceral pain associated with gastrointestinal spasm and colicky conditions.
• Acute trauma pain: delivers strong analgesic effect for injuries such as fractures or severe burns.

• Metamizole sodium exerts its effect by non‑selectively inhibiting cyclooxygenase (COX‑1 and COX‑2) enzymes, which reduces the synthesis of prostaglandins involved in pain signaling and fever generation. The drug also possesses central analgesic activity, likely mediated through modulation of spinal nociceptive pathways and a spasmolytic effect on smooth muscle, contributing to its efficacy in visceral pain such as colic and inflammation.

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

Common Side Effects

• Injection site pain: mild discomfort at the site of intramuscular or intravenous administration.
• Nausea or vomiting: transient gastrointestinal upset.
• Transient hypotension: occasional drop in blood pressure shortly after injection.
• Dizziness or headache: mild central nervous system symptoms.

Serious or Rare Side Effects

• Agranulocytosis: severe reduction of white blood cells that can lead to life‑threatening infections.
• Anaphylactic reaction: rare but possible severe allergic response requiring immediate medical attention.
• Severe skin reactions: such as Stevens‑Johnson syndrome or toxic epidermal necrolysis.

When prescribing Metamizole sodium, clinicians should consider several safety precautions to minimize risk.

• Assess blood counts: obtain baseline and periodic leukocyte monitoring due to risk of agranulocytosis.
• Avoid use in patients with known hypersensitivity to pyrazolones or previous severe reactions.
• Use cautiously in renal or hepatic impairment, adjusting dose as clinically indicated.
• Do not combine with other myelosuppressive agents without close monitoring.
• Pregnancy and lactation: evaluate risk‑benefit, as safety data are limited.
• Store below 25°C: keep in the original pack, protect from moisture.

Metamizole sodium can interact with several medicines, altering efficacy or safety.

Major Interactions (Avoid)

• Cytotoxic chemotherapy agents: increased risk of bone marrow suppression.
• Anticoagulants (e.g., warfarin): potential enhancement of bleeding risk.
• Other NSAIDs or COX inhibitors: additive gastrointestinal toxicity.

Moderate Interactions (Monitor Closely)

• Sulfonamide antibiotics: possible additive hematologic effects.
• ACE inhibitors or diuretics: may potentiate hypotensive episodes.
• Lithium: monitor serum levels as NSAID interaction may raise lithium concentration.