Hypnotic and sedative drugs

Barbiturates represent a class of sedative and hypnotic drugs employed extensively in medicine. RIA provides a rapid, sensitive specific and reliable means for their determination in plasma levels upto 5 ng without indulging in any type of extraction, filtration or evaporation as required for other conventional analytical methods. ... 

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. 

Allgulander C, Ljungberg L, Fisher LD. Long-term prognosis in addiction on sedative and hypnotic drugs analyzed with the Cox regression model. Acta Psychiatr Scand 1987 75 521-531. 

Sedative and hypnotic drugs, such as benzodiazepines and barbiturates, increase the half-life from 50% to 150% in patients between 30 and 70 years of age. The most alarming toxicity is ataxia, which must be considered to avoid accidents. Ataxia is an alarming effect hence the patient is advised not to drive if taking these drugs. Elderly patients are found to be more sensitive to opioids and should use them with caution. 

Dier and sudden unforeseen emotional crisis invariably create such clinical situations that exceptionally demand the essential use of sedatives and hypnotics. A plethora of insomnia (sleeplessness) inadvertently caused due to short-term situational stress is usually regarded as the most suitable and ideal circmnstantial condition(s) which necessiates drug-treatment not only to facilitate but also to augment sleep. After a vigorous and intensive research the introduction of rather newer yet safer and definitely more efficacious sedative and hypnotic drug has always been greeted with great fervour and optimism. 

A. Dantrolene may have additive central nervous system-depressant effects with sedative and hypnotic drugs. 

Some synthetic drugs contain a triple bond. For example, ethinamate is a sedative and hypnotic drug, and tremorine is used to treat Parkinsons disease. 

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

The Summary Drug Table Sedatives and Hypnotics Barbiturates gives examples of the short-, intermediate-, and long-acting barbiturate sedatives and hypnotics. 

SUM MARY DRUG TABLE SEDATIVES AND HYPNOTICS BARBITURATES... 

Although the use of barbiturates and miscellaneous sedatives and hypnotics for sedation has largely been replaced by the antianxiety drugs (see Chap. 30), they occasionally may be used to provide sedation before certain types of procedures such as cardiac catheterization or the administration of a local or general anesthesia Sedative doses usually given during daytime hours, may be used to treat anxiety and apprehension. Fhtients with chronic disease may require sedation, not only to reduce anxiety, but also as an adjunct in the treatment of their disease... 

Adverse reactions associated with administration of the miscellaneous sedatives and hypnotics vary depending on the drug used. Common adverse reactions include dizziness, drowsiness, headache, and nausea Other adverse reactions that may be seen with the administration of miscellaneous sedatives and hypnotics are listed in the Summary Drug Table Miscellaneous Sedatives and Hypnotics. 

Assessment of the patient receiving a sedative or hypnotic drug depends on die reason for administration and whether the drug is given routinely or as needed. 

Use With Alcohol. Alcohol is a CNS depressant, as are the sedatives and hypnotics. When alcohol and a sedative or hypnotic are taken together, there is an additive effect and an increase in CNS depression, which has, on occasion, resulted in death. The nurse must emphasize tiie importance of not drinking alcohol while taking this drug and stress that the use of alcohol and any one of these drains can result in serious effects. 

The roots are used as an astringent, resolving anodyne and antidotal. It is also used to heal abscesses, assuage postpartum pain, and remove parasites from the skin. The plant was mentioned by Schimmel in the American Journal of Pharmacy in 1889. Clinical observation and pharmacological investigation of the sedative and hypnotic effects of the Chinese drug rhizome and root of Patrinia scabiosaefolia are discussed by Luo (43). 

All barbiturates (except phenobarbital) except when used to control seizures Are highly addictive and cause more adverse effects than most sedative or hypnotic drugs in elderly patients. High... 

During the early twentieth century the barbiturates were used in children and adolescents for their sedative and hypnotic effects however, their safety profile and propensity to cause physical dependence led scientists in search of safer anxiolytics. The development of animal models of behavioral disorders facilitated the formulation of drugs with more specific central nervous system (CNS) effects. In 1959, chlordiazepoxide (Librium) was the first benzodiazepine (BZ) to receive a patent. It entered the market in 1960, followed by diazepam (Valium) in 1963. Today, over 35 BZs have been formulated and over 10 are available in the United States (Ballenger, 1995 Hobbs et ah, 1996). 

Unlike benzodiazepines, buspirone is not associated with sedative or abuse problems, but some clinicians have observed that bus-pirone s anxiolytic properties do not appear to be as potent as those of benzodiazepines, particularly in patients who have previously received a benzodiazepine. Because buspirone is not sedating and has no psychomotor effects, it has a distinct advantage over benzodiazepines when optimal alertness and motor performance are necessary. Response to buspirone occurs in approximately 2-4 weeks. Buspirone does not show cross-tolerance with benzodiazepines and other sedative or hypnotic drugs such as alcohol, barbiturates, and chloral hydrate. Therefore, buspirone does not suppress benzodiazepine withdrawal symptoms. In anxious patients who are taking a benzodiazepine and who require a switch to buspirone, the benzodiazepine must be tapered gradually to avoid withdrawal symptoms, despite the fact that the patient is receiving buspirone. 

Sedatives and hypnotics as a group, and BZDs in particular, are frequently implicated in drug-related hospital admissions in the elderly ( 333, 334). This group is at particular risk for abrupt drug discontinuation when hospitalized, with resulting withdrawal symptoms that may be unrecognized as such and attributed to other health problems (313, 335, 336 and 337). BZD hypnotics should not be routinely prescribed in the hospital unless the patient has a demonstrated sleep disorder ( 338). Even then, reassurance that restless sleep is normal in such a situation may obviate the need for a hypnotic ( 330). 

Most sedatives and hypnotics achieve concentrations in breast milk sufficient to produce a pharmacologic effect in some infants. Barbiturates taken in hypnotic doses by the mother can produce lethargy, sedation, and poor suck reflexes in the infant. Chloral hydrate can produce sedation if the infant is fed at peak milk concentrations. Diazepam can have a sedative effect on the nursing infant, but, most importantly, its long half-life can result in significant drug accumulation. 

The sedative and hypnotic effects of methaqualone are greatly increased when the drug is mixed with other CNS depressants such as alcohol or marijuana and can result in coma or death. 

Tetrahydropalmatine has strong analgesic, sedative, and hypnotic effects 544, 553-563). They are produced by the (—) type hut not by the (+) type. In rabbits the analgesic effect was weaker than that of morphine, but the tolerance for this drug developed at a far slower rate practically without any side effects. In experiments on patients tetrahydropalmatine had a weaker analgesic effect but a stronger hypnotic effect than morphine. Application of doses of 10 mg/kg of tetrahydropalmatine to white mice led to disappearance of the conditioned reflexes whereas the unconditioned reflexes were maintained. For the influence of (+ )-tetrahydropalmatine and other alkaloids on gastric ulcers in experimental animals, see Soji et al. (564). Variously substituted tetrahydroberberine and tetrahydropseudoberberine derivatives act as tranquilizers (565-569). 

Kastrup, E. K., ed. Sedatives and Hypnotics, Barbiturates. Drug Facts and Comparisons. St Louis Wolters Kluwers Health, 2005. 977-984. 

Chloral hydrate [KLOR al HYE drate] is a trichlorinated derivative of acetaldehyde that is converted to trichloroethanol in the body. The drug is an effective sedative and hypnotic that induces sleep in about 30 minutes and lasts about 6 hours. Chloral hydrate is irritating to the gastrointestinal tract and causes epigastric distress. It also produces an unusual, unpleasant taste sensation. 

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