Norgesic (Orphenadrine Citrate, Paracetamol)

Norgesic, a combination of a centrally acting muscle relaxant and an analgesic, is used to manage conditions involving musculoskeletal pain and muscle spasm.

• Muscle spasm: reduces involuntary muscle contraction and associated discomfort.
• Back pain: alleviates pain and stiffness in the lumbar region.
• Musculoskeletal pain: provides relief from pain due to strain or injury of muscles and joints.
• Post‑operative pain: helps control pain following surgical procedures.

• Orphenadrine citrate acts as a centrally acting anticholinergic, blocking muscarinic receptors to reduce muscle tone and spasm. Paracetamol exerts analgesic and antipyretic effects by inhibiting cyclooxygenase enzymes within the central nervous system, decreasing prostaglandin synthesis and modulating pain pathways.

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

Common Side Effects

• Drowsiness: feeling unusually sleepy or fatigued.
• Dry mouth: reduced salivation leading to a parched sensation.
• Dizziness: light‑headedness or loss of balance.
• Nausea: upset stomach or urge to vomit.
• Blurred vision: temporary visual disturbances.
• Constipation: difficulty passing stools.

Serious or Rare Side Effects

• Hepatotoxicity: potential liver injury, especially with overdose.
• Severe allergic reaction: rash, swelling, or difficulty breathing.
• Cardiac arrhythmia: irregular heart rhythm.
• Seizures: rare occurrence of convulsive episodes.
• Blood dyscrasias: abnormal blood cell counts.
• Stevens‑Johnson syndrome: severe skin reaction.

Before prescribing Norgesic, clinicians should consider several safety measures.

• Assess liver function: monitor patients with existing hepatic disease.
• Avoid alcohol: concurrent use increases risk of liver injury.
• Use caution in elderly: heightened sensitivity to sedation and anticholinergic effects.
• Review concomitant CNS depressants: may enhance drowsiness.
• Pregnancy: consult a healthcare professional as safety has not been established.
• Store at ambient temperature: keep in the original pack, protect from moisture and heat.

Norgesic can interact with other medicines, requiring careful management.

Major Interactions (Avoid)

• Hepatotoxic drugs (e.g., high‑dose ibuprofen, certain antituberculars): increased risk of liver damage.
• Other anticholinergic agents (e.g., diphenhydramine): additive anticholinergic burden.
• Strong CYP450 inhibitors (e.g., ketoconazole): may raise paracetamol plasma levels.

Moderate Interactions (Monitor Closely)

• Alcohol: can potentiate sedation and hepatic stress.
• CNS depressants (opioids, benzodiazepines): enhanced drowsiness and impaired coordination.
• Warfarin: paracetamol may modestly increase anticoagulant effect, requiring INR monitoring.