Zaleplon

DEA NFLIS-Drug Category -> Depressants and Tranquilizers

DEA Schedule IV Controlled Substance -> Depressants

Pharmaceuticals -> Listed in ZINC15

Pharmaceuticals -> Synthetic Cannabinoids or Psychoactive Compounds

Pharmaceuticals -> Hypnotics

Breast Feeding; Lactation; Milk, Human; Hypnotics and Sedatives

FDA approved drugs -> Active ingredient

FDA approved drugs -> Active ingredient

157-159 °C

157 - 159 °C

Warning

H315 (73.6%): Causes skin irritation [Warning Skin corrosion/irritation]

P203, P260, P261, P263, P264, P264+P265, P270, P271, P280, P302+P352, P304+P340, P305+P351+P338, P318, P319, P321, P332+P317, P337+P317, P362+P364, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 53 reports by companies from 7 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

General symptomatic and supportive measures should be used along with immediate gastric lavage where appropriate. Intravenous fluids should be administered as needed. As in all cases of drug overdose, respiration, pulse, blood pressure, and other appropriate signs should be monitored and general supportive measures employed. Hypotension and CNS depression should be monitored and treated by appropriate medical intervention. (L1712)

Angina pectoris, bundle branch block, hypertension, hypotension, palpitation, syncope, melena, mouth ulceration, rectal hemorrhage, stomatitis, dysphagia, enteritis, gum hemorrhage, diabetes mellitus, goiter, hypothyroidism, arthrosis, bursitis, hyperesthesia, hyperkinesia, hypotonia, incoordination, insomnia, libido decreased, neuralgia, nystagmus, dry skin, eczema, maculopapular rash, skin hypertrophy, dysuria, hematuria, impotence, kidney calculus, kidney pain, urinary retention, and vaginal hemorrhage (RxList, A308). They cause slurred speech, disorientation and "drunken" behavior. They are physically and psychologically addictive. May cause a potentially dangerous rash that may develop into Stevens Johnson syndrome, an extremely rare but potentially fatal skin disease.

In multiple premarketing randomized controlled trials, zaleplon was not associated with an increased rate of serum enzyme elevations in comparison to placebo therapy, and no instance of clinically apparent liver injury was reported. Since its approval and widescale use, zaleplon has not been implicated in causing clinically apparent liver disease. Nevertheless, zaleplon is metabolized in the liver by the cytochrome P450 system (predominantly CYP 3A4) and can cause drug-drug interactions, although such interactions appear to be rare. Thus, zaleplon induced liver injury must be rare, if it occurs at all.

More common adverse effects include drowsiness, dizziness, diarrhea, grogginess, and decreased ability to concentrate. Other less common adverse severe events include abnormal thoughts and behavior, including aggressive behavior, confusion, agitation, hallucinations, worsening of mood issues including worsening depression, suicidal thoughts, memory loss, and severe allergic reactions, including anaphylaxis.

Toxicity in a milder form can cause lethargy, drowsiness, and confusion. Severe toxicity can lead to respiratory depression, ataxia, hypotension, hypotonia, loss of consciousness, coma, and rarely death. Rare cases of fatalities have following overdose with zaleplon have been reported, most of which correlate with the use of other CNS depressants.

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. Organic nitriles decompose into cyanide ions both in vivo and in vitro. Consequently the primary mechanism of toxicity for organic nitriles is their production of toxic cyanide ions or hydrogen cyanide. Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97)

Drug Induced Liver Injury Rank (DILIrank 2.0)

Zaleplon

vNo-DILI-concern

0

No match

DOI:10.1016/j.drudis.2016.02.015

N - Nervous system

QN - Nervous system

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.

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.

Zaleplon is primarily metabolized by aldehyde oxidase.

Zaleplon has known human metabolites that include Dementhylazed-zaleplon.

Zaleplon is primarily metabolized by aldehyde oxidase. Zaleplon is rapidly and almost completely absorbed following oral administration. After oral administration, zaleplon is extensively metabolized, with less than 1% of the dose excreted unchanged in urine. Zaleplon is primarily metabolized by aldehyde oxidase to form 5-oxo-zaleplon. Zaleplon is metabolized to a lesser extent by cytochrome P450 (CYP) 3A4 to form desethylzaleplon, which is quickly converted, presumably by aldehyde oxidase, to 5-oxo-desethylzaleplon. These oxidative metabolites are then converted to glucuronides and eliminated in urine. All of zaleplon's metabolites are pharmacologically inactive (RxList, A308). 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

S62U433RMH

ZALEPLON

Established Pharmacologic Class [EPC] - gamma-Aminobutyric Acid A Receptor Agonist

Mechanisms of Action [MoA] - GABA A Agonists

Physiologic Effects [PE] - Central Nervous System Depression

Zaleplon is a gamma-Aminobutyric Acid A Receptor Agonist. The mechanism of action of zaleplon is as a GABA A Agonist. The physiologic effect of zaleplon is by means of Central Nervous System Depression.

Drugs used to prevent SEIZURES or reduce their severity.

Drugs used to induce drowsiness or sleep or to reduce psychological excitement or anxiety.

Substances that do not act as agonists or antagonists but do affect the GAMMA-AMINOBUTYRIC ACID receptor-ionophore complex. GABA-A receptors (RECEPTORS, GABA-A) appear to have at least three allosteric sites at which modulators act: a site at which BENZODIAZEPINES act by increasing the opening frequency of GAMMA-AMINOBUTYRIC ACID-activated chloride channels; a site at which BARBITURATES act to prolong the duration of channel opening; and a site at which some steroids may act. GENERAL ANESTHETICS probably act at least partly by potentiating GABAergic responses, but they are not included here.

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

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.

1.4 L/kg

1 L/h/kg