CNS depressants alcohol, barbiturates and benzodiazepines

The problems of alcohol dependence and alcoholism are dealt with in Chapter 10. Suffice it to say here that problem drinkers risk numerous psychological problems, such as anxiety and depression, and may experience physical withdrawal symptoms. There are also numerous medical problems related to heavy, chronic alcohol consumption these include increased risk of coronary heart disease, liver cirrhosis, impotence and infertility, cancer and stroke (Chapter 10). It is estimated that alcohol plays a part in up to 33,000 deaths per year in the UK (DoH, 2001). Within the last year 1 in 4 adults will have experienced loss of memory following an alcoholic binge, injured themselves or 

10-20 Detectable increase in feelings of well-being and warmth. 

30-40 Light-headedness feelings of happiness slight exhilaration, feeling more animated  

50-60 Noticeable changes in emotion lowered inhibition impaired judgement lack of 

70-90 Slowed reaction time lack of muscle co-ordination numbness in extremities and 

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Drug interactions Additive CNS depressant effects may occur when antihistamines are administered concomitantly with other CNS depressants, including barbiturates, benzodiazepines, alcohol, and other sedatives. Additive anticholinergic effect also may occur when used in combination with other anticholinergic agents. 

Overdosage Overdosage causes severe respiratory and cardiovascular depression these potentially lethal effects are more likely to occur with alcohols, barbiturates, and carbamates than with benzodiazepines. Management of intoxication requires maintenance of a patent airway and ventilatory support. Flumazenil may reverse CNS depressant effects of benzodiazepines, zolpidem, and zaleplon but has no beneficial actions in overdosage with other sedative-hypnotics. 

Alcohol (ethanol) and other sedative-hypnotics— neither benzodiazepine nor barbiturate in nature— work through mechanisms that are poorly understood. In the past, it was thought that alcohols exerted their CNS-depressant effects directly on neuronal membrane composition and fluidity. These and other high-... 

Sedative-hypnotic drugs and anxiolytic drugs are CNS depressants that are used medically to reduce anxiety and/or induce sleep. They may also be used as anticonvulsants. Phenobarbital, for example, is often the maintenance drug of choice for seizure-prone individuals. In general, the sedative-hypnotic family of drugs includes alcohol, barbiturates, benzodiazepines, and such barbiturate-like drugs as chloral hydrate, glutethi-mide, meprobamate, and methaqualone. 

Two alcoholic valerian extracts were found to potentiate pentobarbital sleeping time in mice (37), and Valdispert, an aqueous extract prepared from V. officinalis (L.), increased the thiopental sleeping time in a dose-dependent manner in rats (16). Based on these animal studies, in vitro studies of valerian s effect on GAB Anergic transmission, as well as the case series reported by Chan and colleagues, valerian would be expected to have at least an additive effect with barbiturates, alcohol, benzodiazepines, and other CNS depressants. 

CNS depressants such as barbiturates, benzodiazepines, and alcohol should also be taken into consideration. 

Numerous CNS drugs including narcotics, analgesics, general anesthetics, antihistamines, phenothiazines, barbiturates, benzodiazepines, sedative-hypnotics, tricyclic antidepressants, alcohol, and muscle relaxants, potentiate the respiratory and CNS depression, sedation, and hypotensive effects of levorphanol. 

Drug interactions metaxalone may augment the effects of alcohol, opioids, benzodiazepines, barbiturates, and other CNS depressants. 

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