Introduction

Zaleplon is a sedative/hypnotic, mainly used for insomnia. It is known as a nonbenzodiazepine hypnotic. Zaleplon interacts with the GABA receptor complex and shares some of the pharmacological properties of the benzodiazepines. Zaleplon is a schedule IV drug in the United States.

Uses

Zaleplon is a sedative used for short term treatment of insomnia in adults.

For the treatment of short-term treatment of insomnia in adults.

Associated Conditions

Insomnia

Pharmacodynamics

Zaleplon is a nonbenzodiazepine hypnotic from the pyrazolopyrimidine class and is indicated for the short-term treatment of insomnia. While Zaleplon is a hypnotic agent with a chemical structure unrelated to benzodiazepines, barbiturates, or other drugs with known hypnotic properties, it interacts with the gamma-aminobutyric acid-benzodiazepine (GABA_BZ) receptor complex. Subunit modulation of the GABA_BZ receptor chloride channel macromolecular complex is hypothesized to be responsible for some of the pharmacological properties of benzodiazepines, which include sedative, anxiolytic, muscle relaxant, and anticonvulsive effects in animal models. Zaleplon also binds selectively to the CNS GABA_A-receptor chloride ionophore complex at benzodiazepine(BZ) omega-1 (BZ1, ο1) receptors.

Mechanism of Action

Zaleplon exerts its action through subunit modulation of the GABA_BZ receptor chloride channel macromolecular complex. Zaleplon also binds selectively to the brain omega-1 receptor located on the alpha subunit of the GABA-A/chloride ion channel receptor complex and potentiates t-butyl-bicyclophosphorothionate (TBPS) binding.

Absorption

Absorption Zaleplon is rapidly and almost completely absorbed following oral administration.

Volume of Distribution

1.4 L/kg

Protein Binding

Approximately 60% (in vitro plasma protein binding).

Route of Elimination

Zaleplon is metabolized primarily by the liver and undergoes significant presystemic metabolism. After oral administration, zaleplon is extensively metabolized, with less than 1% of the dose excreted unchanged in urine. Renal excretion of unchanged zaleplon accounts for less than 1% of the administered dose.

Half Life

Approximately 1 hour

Clearance

1 L/h/kg

Toxicity

Side effects include abdominal pain, amnesia, dizziness, drowsiness, eye pain, headache, memory loss, menstrual pain, nausea, sleepiness, tingling, weakness

Food Interactions

Avoid alcohol. Ingesting alcohol may increase the CNS depressant effects of zaleplon.
Do not take with or immediately after a high-fat meal. The effects of zaleplon are reduced when taken with a high-fat meal.

Dosage

The dose of Zaleplon should be individualized. The recommended dose of Zaleplon for most non elderly adults is 10 mg. For certain low weight individuals, 5 mg may be a sufficient dose. Although the risk of certain adverse events associated with the use of Zaleplon appears to be dose dependent, the 20 mg dose has been shown to be adequately tolerated and may be considered for occasional patient who does not benefit from a trial of lower dose. Dosage above 20 mg has not been adequately evaluated and is not recommended.

Zaleplon should be taken immediately before bedtime. Taking Zaleplon with or immediately after a heavy, high fat meal results in slower absorption and would be expected to reduce the effect of Zaleplon on sleep latency. Elderly patients and debilitated patients appear to be more sensitive to the effects of hypnotic, and respond to 5 mg of Zaleplon. The recommended dose for these patients is therefore 5 mg, doses over 10 mg are not recommended.

For patients with mild to moderate renal impairment, no dose adjustment is necessary.

An initial dose of 5 mg should be given to patients concomitantly taking Cimetidine because Zaleplon clearance is reduced in this population.

Pediatric use: The safety and effectiveness of Zaleplon in pediatric patients have not been established.

Generic Name	Zaleplon
Bangla Name	জালোপলন
Available brands	2

Zaleplon