PAXAM

What it is

PAXAM contains clonazepam. 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.

Approved indications

— Most types of epilepsy in infants and 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), and partial epilepsy (including psychomotor seizures) in adults. — Status epilepticus (intravenous use).

Dosing overview

Dosage must be individually adjusted according to the patient's clinical response and tolerance, and is essentially individualised depending in the first instance on the age of the patient. 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. Average maintenance therapy for infants (up to 2 years) is 0.5–1 mg daily; small children (2–5 years) 1.5–3 mg daily; school children (6–12 years) 3–6 mg daily; and adults 4–8 mg daily, with a maximum daily dose of 20 mg for adults. The maintenance dose should be attained after 2 to 4 weeks of treatment. For status epilepticus, infants and children receive half an ampoule (0.5 mg) by slow intravenous injection or infusion, and adults receive one ampoule (1 mg) by slow intravenous injection or infusion, at a rate not exceeding 0.25 to 0.5 mg per minute.

Key safety warnings

Elderly patients are usually more sensitive to the effects of benzodiazepines; particular care should be taken during up-titration, the lowest possible dose should be used, and the maintenance dose will usually be in the lower range of adult dosage. The concomitant use of PAXAM with alcohol and/or central nervous system depressants has the potential to increase clinical effects, possibly including severe sedation that could result in coma or death, and clinically relevant respiratory and/or cardiovascular depression; patients should abstain from drinking alcohol while under treatment with PAXAM. Transient amnesia or memory impairment has been reported in association with the use of benzodiazepines, with the risk increasing at higher doses. Only a small minority of patients with common seizure types achieves lasting remission with clonazepam; tolerance to the anticonvulsant effect may occur after 4 weeks to 6 months of continuous treatment in the majority of patients, and increasing the dose in this situation is rarely worthwhile; if seizures are no longer being adequately controlled, the medicine should be discontinued and alternative treatment implemented. The use of benzodiazepines may lead to development of physical and psychological dependence, with the risk of dependence increasing with dose and duration of treatment and being greater in patients with a medical history of alcohol and/or drug abuse. Treatment with PAXAM must not be stopped abruptly, but must be reduced in a stepwise fashion.

Contraindications

PAXAM is contraindicated in patients with a known hypersensitivity to clonazepam, benzodiazepines or any of the excipients of PAXAM. PAXAM is contraindicated in patients with chronic obstructive airways disease with incipient respiratory failure, severe hepatic impairment, and dependence on drugs of abuse and central nervous system depressants including alcohol.

PBS listing

PAXAM tablets 500 micrograms are listed on the PBS with 2 items, authority required restriction, and ex-manufacturer price of A$6.30. PAXAM tablets 2 mg are listed on the PBS with 2 items, authority required restriction, and ex-manufacturer price of A$8.83.

Regulatory history

PAXAM was first approved on 23 August 1991. ARTG registrations for PAXAM 0.5 mg and 2 mg tablets (sponsored by Alphapharm) were first listed on 28 May 1996.