Norgesic (Orphenadrine Citrate, Paracetamol)

• Norgesic is indicated for conditions involving skeletal muscle spasm and associated pain, acting as a combined muscle relaxant and analgesic.
• Muscle spasm: reduction of involuntary muscle contraction and associated discomfort.
• Acute musculoskeletal pain: relief of pain arising from soft tissue injury or strain.
• Back pain: alleviation of low‑back muscle tension and pain.
• Neck pain: improvement of cervical muscle stiffness and pain.

• Orphenadrine citrate exerts central anticholinergic activity by blocking muscarinic receptors, which diminishes skeletal muscle hyperactivity and produces relaxation. Paracetamol contributes analgesia primarily through inhibition of central cyclo‑oxygenase enzymes, reducing prostaglandin synthesis in the brain and modulating pain pathways. The combined effect provides both muscle relaxation and pain relief without significant peripheral anti‑inflammatory activity. Additionally, the formulation may enhance central analgesic pathways through serotonergic modulation.

Adverse reactions reported with Norgesic vary in frequency and severity.

Common Side Effects

• Drowsiness: feeling of sleepiness or reduced alertness.
• Dry mouth: decreased salivation causing oral discomfort.
• Dizziness: sensation of light‑headedness or imbalance.
• Nausea: feeling of queasiness, sometimes leading to vomiting.

Serious or Rare Side Effects

• Severe allergic reaction: rash, swelling, or angioedema requiring immediate medical attention.
• Hepatotoxicity: elevated liver enzymes or liver injury, especially with prolonged use.
• Cardiac arrhythmia: irregular heart rhythm that may be life‑threatening.

• Before prescribing Norgesic, clinicians should consider several safety measures.
• Assess liver function: monitor hepatic enzymes before and during therapy.
• Avoid in patients with known hypersensitivity to orphenadrine or paracetamol.
• Use caution in the elderly: increased risk of sedation and falls.
• Limit concurrent alcohol intake: may enhance hepatotoxic risk.
• Avoid driving or operating machinery: potential drowsiness.
• Store at ambient temperature: keep in original container, protect from moisture and light.

Norgesic may interact with other medicines; awareness of potential interactions helps ensure safe use.

Major Interactions (Avoid)

• MAO inhibitors: risk of hypertensive crisis.
• Other anticholinergic agents: additive anticholinergic effects.
• Alcohol: increased sedation and hepatotoxicity.

Moderate Interactions (Monitor Closely)

• CYP450 inhibitors (e.g., fluconazole): may raise plasma levels.
• Anticoagulants (e.g., warfarin): possible enhancement of bleeding risk.