RIVOTRIL

What it is

RIVOTRIL contains clonazepam, available as tablets of 0.5 mg or 2 mg. Clonazepam is an anticonvulsant which exhibits several pharmacological properties characteristic of the benzodiazepine class of medicines. Benzodiazepines enhance the polysynaptic inhibitory processes at all levels of the central nervous system, and clonazepam is more effective in blocking spread of electrical activity in the lesion itself.

Approved indications

— Most types of epilepsy in children, especially absences (petit mal), myoclonic seizures and tonic-clonic fits, whether due to primary generalised epilepsy, or to secondary generalisation of partial epilepsy. — All varieties of generalised epilepsy (including myoclonic, akinetic, tonic and tonic-clonic seizures) in adults. — Partial epilepsy (including psychomotor seizures) in adults.

Dosing overview

Dosage of clonazepam is individualised and depends in the first instance on the age of the patient, determined according to clinical response and tolerance. It is essential to commence with low doses and increase the daily dose progressively until a maintenance dose suited to the individual patient has been reached. Initiation dosing is: children aged 2 to 5 years, 0.5 mg per day (half a 0.5 mg tablet morning and evening); children aged 6 to 12 years, 0.75 mg per day (half a 0.5 mg tablet in the morning, one 0.5 mg tablet in the evening); adults, 1 mg per day (one 0.5 mg tablet morning and evening). Average maintenance dosage ranges are: small children aged 2 to 5 years, 1.5–3 mg daily; school children aged 6 to 12 years, 3–6 mg daily; adults, 4–8 mg daily. The maximum daily dose for adults is 20 mg per day. The maintenance dose should be attained after 2 to 4 weeks of treatment. Elderly patients are usually more sensitive to the effects of benzodiazepines, and particular care should be taken during up-titration in elderly patients, with the lowest possible dose used in the elderly.

Key safety warnings

The concomitant use of clonazepam with alcohol and/or central nervous system depressants has the potential to increase the clinical effects of clonazepam, possibly including severe sedation that could result in coma or death, and clinically relevant respiratory and/or cardiovascular depression. Since alcohol can provoke epileptic seizures irrespective of therapy and may potentiate the central nervous system depressant effects of clonazepam, it is imperative that patients should abstain from drinking alcohol while under treatment with clonazepam. Transient amnesia or memory impairment has been reported in association with the use of benzodiazepines, and the risk increases with higher doses. Benzodiazepines are not recommended for use in patients with sleep apnoea due to possible additive effects on respiratory depression; sleep apnoea appears to be more common in patients with epilepsy, and clonazepam should only be used in epileptic patients with sleep apnoea when the expected benefit exceeds the potential risk. The use of benzodiazepines may lead to development of physical and psychological dependence, and the risk of dependence increases with dose and duration of treatment and is greater in patients with a medical history of alcohol and/or drug abuse. RIVOTRIL should be terminated by tapering the dose to minimise the occurrence of withdrawal symptoms. Only a small minority of patients with the common seizure types achieves a lasting remission with clonazepam, and tolerance to the anticonvulsant effect may occur after 4 weeks to 6 months of continuous treatment, leading to increased seizure frequency.

Contraindications

Clonazepam is contraindicated in patients with known hypersensitivity to benzodiazepines, known hypersensitivity to any of the excipients in RIVOTRIL, chronic obstructive airways disease with incipient respiratory failure, dependence on drugs of abuse and central nervous system depressants including alcohol, and severe hepatic impairment as benzodiazepines may precipitate hepatic encephalopathy.

PBS listing

The tablet 500 micrograms strength is listed on the PBS with 2 items, restriction type authority required or restricted, at an ex-manufacturer price of A$4.01.

Regulatory history

RIVOTRIL clonazepam tablets are registered on the Australian Register of Therapeutic Goods with AUST R 54846 for the 0.5 mg tablet and AUST R 54847 for the 2 mg tablet. The oral liquid 2.5 mg per mL was first listed on the ARTG on 1991-08-23, the injection 1 mg in 2 mL was first listed on 1991-08-23, and the tablet 0.5 mg was first listed on 2017-05-24.