Sedative hypnotic drugs actions

CNS-depressant effects Zolpidem, like other sedative/hypnotic drugs, has CNS-depressant effects. Because of the rapid onset of action, only ingest immediately prior to going to bed. Zolpidem had additive effects when combined with alcohol therefore, do not take with alcohol. 

Buspirone causes less psychomotor impairment than benzodiazepines and does not affect driving skills. The drug does not potentiate effects of conventional sedative-hypnotic drugs, ethanol, or tricyclic antidepressants, and elderly patients do not appear to be more sensitive to its actions. Nonspecific chest pain, tachycardia, palpitations, dizziness, nervousness, tinnitus, gastrointestinal distress, and paresthesias and a dose-dependent pupillary constriction may occur. Blood pressure may be significantly elevated in patients receiving MAO inhibitors. 

Benzodiazepines, barbiturates, and most older sedative-hypnotic drugs exert calming effects with concomitant reduction of anxiety at relatively low doses. In most cases, however, the anxiolytic actions of sedative-hypnotics are accompanied by some depressant effects on psychomotor and cognitive functions. In experimental animal models, benzodiazepines and older sedative-hypnotic drugs are able to disinhibit punishment-suppressed behavior. This disinhibition has been equated with antianxiety effects of sedative-hypnotics, and it is not a characteristic of all drugs that have sedative effects, eg, the... 

Blocks actions of benzodiazepines and zolpidem but not other sedative-hypnotic drugs... 

Several drugs with novel chemical structures have been introduced recently. Buspirone is an anxiolytic agent that has actions different from those of conventional sedative-hypnotic drugs. Zolpidem and zaleplon, while structurally unrelated to benzodiazepines, share a similar mechanism of action. 

Triazolam, USP. Triazolam. 8-chloro-6-(o-chlorophc-nyl)-l-methyl-4Ay-j-triaz.olol4.3-a f l,4 benzxxliazcpinc (Hal-cion). has all of the characteristic benzodiazepine pharmacological actions. It is marketed as a sedative-hypnotic drug said to impair little, if any. daytime function. It is rapidly metabolized to the I-methyl alcohol, which is then conjugated and excreted. 

Overall the anthiistamines are relatively safe. However, their CNS depressant actions are enhanced by co-ingestion of ethanol, sedative-hypnotic drugs, and opioids their anticholinergic actions are potentiated by co-ingestion of tricyclic antidepressants and phenothiazines. Therefore the... 

Meprobamate is a bis-carbamate ester it was introduced as an antianxiety agent in 1955, and this remains its only approved use in the United States. However, it also became popular as a sedative-hypnotic drug, and it is discussed here mainly because of its continued use for such purposes. The question of whether the sedative and antianxiety actions of meprobamate differ is unanswered, and clinical proof of the ef cacy of meprobamate as a selective antianxiety agent in human beings is lacking. 

Since there was some evidence that these compounds owe their action to interference with the action of histamine, this class has earned the soubriquet "antihistamines." This class of drugs is further characterized by a spectrum of side effects which occur to a greater or lesser degree in various members. These include antispasmodic action, sedative action, analgesia, and antiemetic effects. The side effects of some of these agents are sufficiently pronounced so that the compounds are prescribed for that effect proper. Antihistamines, for example, are used as the sedative-hypnotic component in some over-the-counter sleeping pills. 

A class of sedative/hypnotic type drug that exert their effects through the benzodiazepine binding site on GABAa receptors. The class consists both of molecules that contain the benzodiazepine moiety, for example diazepam, lorazepam and flunitrazepam, and the newer, non-benzodiazepine compounds such as zolpidem, zopiclone, indiplon and zaleplon. BzRAs are primarily used for the treatment of anxiety, insomnia and to elicit varying levels of sedation. The wide selection of compounds currently available affords the prescribing clinician extensive options in terms of relative efficacies and durations of action. 

Discuss the uses, general drug actions, adverse reactions, contraindications, precautions, and interactions of the barbiturates and miscellaneous sedatives and hypnotics. 

Ultimately, it is a drug s half-life combined with its potency that dictates its utility as a sedative-hypnotic. Like other benzodiazepines, clonazepam (Klonopin) can be used to treat insomnia, but its long duration of action renders it prone to hangover effects at doses needed to treat insomnia. Nevertheless, low doses of clonazepam (0.25-2 mg) are a treatment for PLMD and are also used to treat RLS. When hangover effects of even low doses of clonazepam are a problem, other benzodiazepines can be used. 

Sedation is an intermediate degree of CNS depression, while hypnosis is a degree of CNS depression similar to natural sleep. From the chemical point of view, soporific, sedative, and hypnotic drugs are classified as barbiturates, benzodiazepine hypnotics, and so on. Except for a few rare exceptions, any one of these compounds can be used for acquiring a sedative effect or state of sleep. Presently, the less toxic benzodiazepines are edging out the class of barbiturates more and more because of the possibility of chronic dependence associated with the use of barbiturates. Drugs of both classes are primarily CNS depressants, and a few of their effects, if not all, are evidently linked to action on the GABA-receptor complex. 

The sedative-hypnotic action of chloral hydrate should be explained by the formation of trichloroethanol, which is synthesized as a result of its reduction in tissues. Despite the fact that the precise mechanism of action of chloral hydrate is not known, it evidently acts analogous to ethanol on the CNS by inCTeasing membrane permeability, which leads to sedation or sleep. Chloral hydrate can be used for insomnia as an alternative to benzodiazepines. Synonyms for this drug are aquachloral, chloradorm, chloratol, noctec, and others. 

As already noted, there are drugs found among benzodiazepine derivatives that have expressed anxiolytic action and that lack or have poorly expressed sedative-hypnotic effects, which are called daytime tranquilizers. Medazepam, a representative of the daytime tranquilizers, is a drug that differs from diazepam only in the absence of a carbonyl group in the seven-membered azepine ring. 

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