Overview
Orphenadrine Citrate/Paracetamol is a combination medication containing a centrally-acting skeletal muscle relaxant (orphenadrine) and an analgesic/antipyretic (paracetamol/acetaminophen). It is primarily used for the relief of acute painful musculoskeletal conditions associated with muscle spasm.
Mechanism of Action
Orphenadrine citrate acts as a centrally-acting anticholinergic agent that produces skeletal muscle relaxation through inhibition of cerebral motor neurons and possibly via atropine-like effects. Paracetamol (acetaminophen) acts as an analgesic and antipyretic through inhibition of prostaglandin synthesis in the central nervous system, with minimal anti-inflammatory effects.
Indications
- Relief of acute painful musculoskeletal conditions associated with muscle spasm
- Muscle pain
- Back pain
- Muscle spasms
Dosage
Typically 1-2 tablets every 6-8 hours as needed for pain. Maximum daily dose should not exceed 8 tablets (4000 mg paracetamol). Duration should be limited to short-term use (usually 2-3 weeks).
Contraindications
- Hypersensitivity to orphenadrine, paracetamol, or any component
- Glaucoma
- Prostatic hypertrophy or bladder neck obstruction
- Myasthenia gravis
- Severe hepatic impairment
- Concurrent use with monoamine oxidase inhibitors (MAOIs)
Side Effects
- Drowsiness
- Dizziness
- Dry mouth
- Blurred vision
- Nausea
- Constipation
- Headache
- Tachycardia
- Urinary retention
- Rash
- Hepatotoxicity (with overdose)
Interactions
- Alcohol (increased CNS depression)
- Anticholinergic drugs (additive effects)
- CNS depressants (sedatives, hypnotics, opioids)
- Monoamine oxidase inhibitors (MAOIs)
- Warfarin (potential increased INR with chronic high-dose paracetamol)
- Drugs metabolized by CYP2E1