Orphenadrine and Paracetamol

Muscle Relaxant · Central anticholinergic (skeletal muscle relaxant)/Para-aminophenol derivative

Indications

Acute and chronic painful muscular conditions, tension, headache, dysmenorrhoea, non-articular rheumatism.

Dosage

Tab 35 mg/450 mg: Adults: 2 tab 3 times daily. Children: Not recommended. Tab 50 mg/650 mg: Adults: 1 tab 3 times daily. Children: Not recommended.

Adverse Effects

ORPHENADRINE: Dry mouth, nausea, blurred vision, dizziness, confusion, tremor, GI upset, restlessness. PARACETAMOL: Rarely, blood disorders.

Risk Factor (Pregnancy/Lactation)

Pregnancy: Risk cannot be ruled out. Lactation: Caution advised or effect undetermined. Contraindications: ORPHENADRINE: Glaucoma, urinary retention, Myasthaenia gravis, prostatic hypertrophy, porphyria, tardive dyskinesia, GI obstruction. PARACETAMOL: Renal or hepatic impairment, alcoholism, chronic malnutrition, dehydration, wt <50 kg, G6PD deficiency, haemolytic anaemia. Risk of serious skin reactions; warn patient of symptoms and discontinue if occur. Precautions: Tachycardia, renal, hepatic or cardiac impairment, hypertension, micturition disorders. Elderly. Withdraw gradually.

Interactions

ORPHENADRINE: TCADs, amantadine, antihistamines, phenothiazines, antispasmodics, disopyramide, other anticholinergics. PARACETAMOL: Metoclopramide, oral anticoagulants, domperidone, colestyramine, busulfan, hepatotoxic drugs, zidovudine, alcohol.

Advice to Patient

Take with or without meals. To prevent GI upset, take with meals.

Pharmacokinetics

ORPHENADRINE: Onset: 1 hr. Duration: 4-6 hrs. Absorption: Oral: Readily absorbed from the GI tract. Metabolism: Hepatic. Half-life elimination: 14 hrs. Time to peak, plasma: 2-4 hrs. Excretion: Urine (mainly). PARACETAMOL: Onset of action: Oral: <1 hr. IV: Analgesia: 5-10 min. Antipyretic: Within 30 min. Peak effect: IV: Analgesic: 1 hr. Duration: IV, Oral: Analgesia: 4-6 hrs. IV: Antipyretic: =6 hrs. Absorption: Primarily absorbed in small intestine, minimal absorption from stomach (varies by dosage form). Metabolism: Hepatic. Half-life elimination: Neonates: 7 hrs. Infants: Approx. 4 hrs. Children: 3 hrs. Adolescents: Approx. 3 hrs. Adults: Approx. 2 hrs. CrCl<30 mL/min: 2-5.3 hrs. Time to peak, serum: Immediate release: 10-60 min. IV: 15 min. Excretion: Urine.

Compiled by Healify Pharmacy from published drug references. How we compile it →

Always consult a pharmacist or doctor.