Abbreviated Prescribing Information: Primidone Rosemont 250mg/5ml Oral Suspension.
Consult Summary of Product Characteristics before prescribing.
Presentation: White to off-white oral suspension with each 5 ml containing 250mg of primidone. Therapeutic Indications: Primidone is indicated for the management of grand mal and psychomotor (temporal lobe) epilepsy and management of focal or Jacksonian seizures, myoclonic jerks, akinetic attacks, and essential tremor. Posology: Primidone should be initiated at the lowest possible dose and titrated gradually according to clinical response to minimise adverse reactions; it may be used as monotherapy or in combination with other anticonvulsants. In adults with epilepsy, treatment usually starts at 125 mg (2.5 mL) daily and is increased stepwise every 3 days until seizure control is achieved or the maximum tolerated dose (up to 1.5 g/day), with maintenance doses of 750–1500 mg (15–30 mL) daily; for essential tremor, treatment starts at 50 mg (1 mL) daily and is gradually increased up to a maximum of 750 mg (15 mL) daily. In paediatric patients from 4 weeks of age and body weight >4 kg, dosing is increased stepwise every 3 days until seizure control or the maximum tolerated dose is reached, with maintenance doses of 250–500 mg daily in children up to 2 years, 500–750 mg daily in children 2–5 years, 750–1000 mg daily in children 6–9 years, and 750–1500 mg daily in children over 9 years. Primidone is for oral administration, and dose adjustment may be required in patients with renal or severe hepatic impairment; elderly patients, particularly those with reduced renal function, should be monitored during treatment. Contra-indications: Hypersensitivity to the active substance primidone, to phenobarbital or to any of the excipients, acute intermittent porphyria, concomitant use with certain classes of medicinal products (refer to the SmPC for the listed classes / product), and in children less than 4 weeks of age and with a body weight of 4kg or less, because of the potential adverse effects/toxicity from the excipient propylene glycol. Special Warnings and Precautions for use: Primidone is not effective in absence seizures and myoclonic fits and may aggravate these conditions. Treatment should be initiated gradually at the lowest possible dose due to sedative effects, and used with caution in children, elderly or debilitated patients, and those with renal, hepatic or respiratory impairment. Abrupt withdrawal should be avoided due to the risk of seizures, status epilepticus, tolerance, dependence and withdrawal reactions. Primidone may increase the risk of osteomalacia, vitamin D deficiency and, rarely, megaloblastic anaemia during long-term treatment. Suicidal ideation and behaviour have been reported with antiepileptic drugs, including primidone, and patients should be monitored accordingly. Serious skin reactions including Stevens–Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS) have been reported, particularly during the first weeks of treatment; primidone should be discontinued immediately if signs or symptoms occur and must not be reintroduced in affected patients. Primidone may cause foetal harm and should only be used in women of childbearing potential when benefits outweigh risks; effective contraception is required during treatment and for 2 months after discontinuation due to reduced efficacy of hormonal contraceptives from enzyme induction. Primidone is an enzyme inducer and may reduce the efficacy of concomitant medicines; concomitant alcohol use is not recommended. Primidone may cause delayed allergic reactions due to presence of methyl and ethyl hydroxybenzoate. Primidone should be used with caution in case of sugar intolerance due to presence of liquid maltitol. The product also contains negligible sodium, and benzoic acid which may increase jaundice in newborns. Any warning from the MC, CHM CSM or MHRA: No. Black Triangle notice: Not applicable. A list of common and serious adverse reactions: Common adverse reactions: Visual disturbances, apathy, ataxia, nystagmus and nausea. Serious adverse reactions: Maculopapular, morbilliform or scarlatiniform rashes, megaloblastic anaemia, leucopenia, thrombocytopenia, lymphadenopathy, psychotic reactions, Dupuytren’s contracture, exfoliative dermatitis, lupus erythematosus, SJS, TEN, hypersensitivity syndrome, osteoporosis and bone fracture, suicidal ideation, confusional state, hallucination, and DRESS. Refer to the SmPC for full details of adverse reactions. Legal Category: Prescription Only Medicine. Pack Size and NHS Price: 150 mL- £205. Marketing Authorisation Number: PL 00427/0303. Marketing Authorisation Holder: Rosemont Pharmaceuticals Limited, Rosemont House, Yorkdale Industrial Park, Braithwaite Street, Leeds, LS11 9XE, UK. Date of Preparation: 05 Jun 2026.