Paracetamol, orphenadrine citrate.
Each tablet contains 450 mg of Paracetamol and 35 mg of Orphenadrine Citrate.
Pharmacology: Pharmacodynamics: Paracetamol, a para-aminophenol derivative, is a peripherally acting analgesic with antipyretic and weak anti-inflammatory activity.
Orphenadrine, an analog of diphenhydramine, is a skeletal muscle relaxant and is postulated to act on cerebral motor center or on the medulla through an atropine-like central action. It has anticholinergic, local anaesthetic effects and some antihistaminic effects. Orphenadrine is used either as the hydrochloride or the citrate and doses are expressed in terms of the relevant salt.
Pharmacokinetics: Absorption: Paracetamol: Absorbed readily from GI tract; time to peak plasma concentrations: 10-60 minutes.
Orphenadrine: Absorbed readily from GI tract and after IM inj.
Distribution: Paracetamol: Distributed into most body tissues including breast milk, crosses the placenta; plasma-protein binding: negligible (but dose dependent).
Orphenadrine: May cross placenta.
Metabolism: Paracetamol: Undergoes hepatic metabolism; a minor metabolite, produced in minute amounts by cytochrome P450 isoenzymes in the liver and kidney, is usually removed by conjugation with glutathione, but may accumulate and cause tissue damage in paracetamol overdosage.
Orphenadrine: Metabolised to ≥8 metabolites.
Excretion: Paracetamol: Excreted in the urine mainly as the glucuronide and sulfate conjugates with <5% excreted unchanged; elimination half-life: 1-3 hr.
Orphenadrine: Excreted mainly in urine and unchanged drug (small amounts); half-life: 14 hr.
Painful skeletal muscle spasm associated w/ chronic low back pain, sprains & strains, prolapsed intervertebral disc, muscle injury, non-articular rheumatism, whiplash injury, acute torticollis, tension headache, dysmenorrhea & other painful muscular conditions.
1 to 2 tablets three times a day. May be taken with or without food. May be taken with meals if GI upset occurs.
Paracetamol: Symptoms: Paleness, nausea, vomiting, anorexia, abdominal pain, metabolic acidosis and glucose metabolism disturbances. Liver damage may surface 12-48 hr after overdose. In severe cases, encephalopathy, haemorrhage, hypoglycaemia, cerebral oedema, acute renal failure and death.
Management: Immediate medical treatment even if there are no symptoms. If presented within 1 hr of poisoning, administer activated charcoal. If needed, administer IV N-acetylcysteine or oral methionine.
Orphenadrine: Symptoms: Vomiting, gastric irritation, dilated pupils, pruritus, urinary retention, tachycardia, hyperpyrexia, euphoria, hallucinations, agitation, paranoid reactions, tremor, excitement, confusion, delirium, circulatory and respiratory failure, coma and convulsions.
Management: Treatment is symptomatic and supportive.
Glaucoma; myasthenia gravis; prostatic hypertrophy or bladder neck obstruction. Children <12 yr.
Cardiac arrhythmias, tachycardia, cardiac decompensation, coronary insufficiency. Monitor blood, urine & liver function w/ prolonged use. May impair the ability to drive or operate machinery. Pregnancy.
Since safety of the use of this preparation in pregnancy, during lactation, or in the childbearing age has not been established, use of the drug in such patients requires that the potential benefits of the drug be weighed against its possible hazard to the mother and child.
Dry mouth, nausea, constipation, tachycardia, palpitation, urinary hesitancy or retention, blurred vision, mydriasis, increased ocular tension, weakness, headache, dizziness and drowsiness.
Potentially Fatal: Blood dyscrasias (rare).
Increased paracetamol absorption with metoclopramide and domperidone. Decreased paracetamol absorption with cholestyramine. May increase risk of bleeding with warfarin and coumarins. Increased anticholinergic side effects with other anticholinergic drugs. Additive CNS effects with propoxyphene. Increased bupropion levels with concurrent use. May antagonize actions of centrally acting anticholinesterases e.g. donepezil, galantamine, rivastigmine, tacrine. May decrease levodopa absorption with concurrent use.
Potentially Fatal: Increased risk of liver damage with alcohol.
Store at temperatures not exceeding 30°C.
M03BC51 - orphenadrine, combinations ; Belongs to the class of ethers. Used as centrally-acting muscle relaxants.
Sign Out
