Mysoline

What is it?

An antieonvulsant pyrimidinedone preparation available as scored, white tablets containing 250mg of primidone, marked with M on each side of score line.

Medical Uses

Epilepsy.

Dosage

Adults, 125mg taken at night in first instance increasing every 3 days by 125mg to 500mg each day. Then a further increase every third day of 250mg to a maximum dose of 1.5g daily. Children, same initial dose as adults but only increasing by 125mg increments. Usual daily maintenance doses as follows: up to 2 years, 250500mg; 2 to 5 years, 500-750mg; 6 to 9 years, 750mg-1g; 9 to 12 years, 750mg-1.5g.

Special Care

Liver, kidney and lung disorders.

Avoid Use

Pregnancy, breast-feeding, elderly, patients who are debilitated, acute, intermittent porphyria, pain which is not controlled, history of drug or alcohol abuse.

Possible Drug and Food Interactions

Cns depressants, griseofulvin, alcohol, phenytoin, systemic steroids, chloramphenicol, rifampicin, metronidazole, anticoagulants of the coumarin type.

Known Side Effects

Headache, nausea, respitatory depression, dizziness, unsteadiness and lack of co-ordination (withdraw drug if severe), sleepiness, confusion, agitation, nystagmus (involuntary eye movements), disturbance of vision, allergic responses. Dupuytren's contracture (abnormal thickening of palm causing bending and stiffening of 4th and 5th fingers). Drug tolerance and dependence may occur - as drug is partially metabolized to phenobarbitone (a barbiturate).

Manufacturer

Astrazeneca.