Composition: Zaleplon 5mg and 10mg.
Presentation: Hard capsules, 5mg white and light brown with gold band, 10mg white with pink band.
Storage and stability: Do not store above 30C.
Action: Short-acting pyrazolopyrimidine hypnotic.
Indications: The treatment of patients with insomnia who have difficulty falling asleep. Zaleplon is indicated only when the disorder is severe, disabling or subjecting the individual to extreme distress.
Contraindications: Severe hepatic insufficiency, hypersensitivity to the active substance or to any of the excipients, sleep apnoea syndrome, myasthenia gravis, severe respiratory insufficiency.
Dosage and administration: Treatment should be as short as possible, with a maximum duration of two weeks. Zaleplon can be taken immediately before going to bed or after the patient has gone to bed and is experiencing difficulty sleeping. The total dose should not exceed 10mg in any patient. Patients should be advised not to take a second dose within a single night. Administration after food delays time to maximal plasma concentration by approximately two hours; however, the total extent of absorption is not altered.
Adults, recommended dose 10mg. Elderly, recommended dose 5mg. Children under 18 years of age, not recommended as no data are available.
Mild to moderate hepatic impairment, should be treated with 5mg as clearance is reduced.
Renal insufficiency, no dosage adjustment required.
Pregnancy, insufficient data are available to assess the safety of zaleplon during pregnancy and lactation. See SPC for details on use during pregnancy. Zaleplon is excreted in breast milk and should not be given to breast-feeding mothers.
Overdosage: Limited clinical experience with the effects of acute overdose. Overdosage should not present a threat to life unless combined with other CNS depressants (including alcohol). Following overdose, vomiting should be induced (within one hour) if the patient is conscious. If the patient is unconscious, gastric lavage should be undertaken with the airway protected. Activated charcoal should be given where there is no advantage in emptying the stomach. Flumazenil may be useful as an antidote.
Precautions: Patients should be advised not to take a second dose within a single night. Alternative therapy should be considered if early morning awakening is experienced.
Loss of efficacy may develop after repeated use. Also, use may lead to physical and psychic dependence. On withdrawal a transient syndrome may occur, whereby the symptoms that led to treatment recur. Pre-existing depression may be unmasked during treatment with benzodiazepines or benzodiazepine-like agents. Use with extreme caution in patients with a history of alcohol or drug abuse. Caution should also be taken with use in patients with chronic respiratory insufficiency.
Drug interactions: Concomitant intake with alcohol is not recommended. Enhancement of sedation may occur in cases of concomitant use with antipsychotics (neuroleptics), anxiolytics/sedatives, hypnotics, antidepressants, narcotic analgesics, anti-epileptics, anaesthetics and sedative antihistamines. Caution is advisable in co-administering zaleplon with cimetidine, ketoconazole and erythromycin. Rifampicin, carbamazepine and phenobarbitone may result in a reduction of zaleplon's efficacy.
Side effects: In placebo-controlled trials, 6 per cent of patients treated with zaleplon and 4 per cent treated with placebo experienced somnolence. The most apparent undesirable effects are a mild headache, asthenia, somnolence and dizziness. Anterograde amnesia may occur using recommended therapeutic dosages, the risk increasing at higher doses. Reactions such as restlessness, agitation, irritability, aggressiveness, delusions, rages, nightmares, hallucinations, psychoses, inappropriate behaviour and other adverse behavioural effects are known to occur when using benzodiazepines or benzodiazepine-like agents.
Net price: 5mg 14 £2.80, 10mg 14 £3.36.
Supplier: Wyeth Laboratories, Huntercombe Lane South, Taplow, Maidenhead, Berkshire SL6 0PH. Tel 01628 604377, fax 01628 667599. For medical information contact Lundbeck Ltd, tel 01908 649966.
Legal class: POM.