Zaleplon

Zaleplon (marketed under the brand names Sonata and Starnoc) is a sedative/pyrazolopyrimidine class.

Chemistry

Pure zaleplon in its solid state is a white to off-white powder that has very low pH range is between 1 and 7.

Pharmacology

Taken orally, zaleplon reaches full concentration in approximately one hour. It is extensively metabolised, into 5-oxo-zaleplon and 5-oxo-desethylzaleplon (the latter via desethylzaleplon), with less than 1% of it excreted intact in urine.

Zaleplon interacts with the benzodiazepine, zaleplon can cause similar effects: anterograde amnesia (forgetting the period during the effects) as the most common.

Zaleplon is primarily metabolised by aldehyde oxidase, and its half-life can be affected by substances which inhibit or induce aldehyde oxidase.

A meta-analysis of randomised controlled clinical trials which compared benzodiazepines against Zaleplon or other Z Drugs such as benzodiazepines in terms of sleep onset latency, total sleep duration, number of awakenings, quality of sleep, adverse events, tolerance, rebound insomnia and daytime alertness.^[1]

Zaleplon has a pharmacological profile similar to benzodiazepines, that is characterized by an increase in SWDS with rapid onset of hypnotic action. Zaleplon is a selective full agonist for the EEG power density in the delta frequency band and a decrease in the energy of the theta frequency band. In tests on rabbits zaelplon shows drowsy pattern of spontaneous EEG characterized by high-voltage slow waves and desynchronization of hippocampal theta waves and an increase in the energy of the delta frequency band on the spectral analysis of the electroencephalogram.^[2]

Side-effects

Zaleplon may cause hallucinations, abnormal behavior, severe confusion, day-time drowsiness, dizziness or lightheadedness, unsteadiness and/or falls, double vision or other vision problems, agitation, headache, nausea, vomiting, diarrhea or abdominal pain, depression, muscle weakness, tremor, vivid or abnormal dreams and memory difficulties or amnesia.

Zaleplon is habit-forming, meaning addiction may occur. Stopping this medication suddenly after prolonged or frequent use may cause withdrawal effects such as mood changes, anxiety, and restlessness.

Recreational use

Zaleplon (Sonata) has a relatively high potential to be abused. Often this use involves a different delivery method (insufflation) to induce effects faster.  

The side effects of zaleplon are greatly increased when taken improperly, especially retrograde amnesia - the inability to remember the time during which one was under the influence of the drug. Zaleplon is a benzodiazepine drugs, but that they still carried a risk higher than first believed. The study specifically mentions persons with prior substance abuse problems as individuals with a high risk for addiction to nonbenzodiazepine type drugs. ^[3]

References