Anxiolytic drugs withdrawal problems

The speciflc clinical use of the numerous available benzodiazepines depends on their individual pharmacokinetic and pharmacodynamic properties. Drugs with a high affinity for the GABAa receptor (alprazolam, clonazepam, lorazepam) have high anxiolytic efficacy drugs with a short duration of action (temazepam) are used as hypnotics to minimise daytime sedative effects. Diazepam has a long half-life and duration of action and may be favoured for long-term use or when there is a history of withdrawal problems oxazepam has a slow onset of action and may be less susceptible to abuse. 

This section describes the partial agonists and the nonbenzodiazepine drugs that act at the benzodiazepine receptor. What these drugs have in common is that their development has been driven by the search for effective anxiolytics that do not have the adverse effects of sedation, amnesia, ataxia, interaction with alcohol, or the problems of tolerance, dependency, and withdrawal seen with classic benzodiazepines. These problems have been addressed by the development of partial agonists, subtype-selective ligands, and other drugs, the cyclopyrrolones, which do not seem to cause these problems. 

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. 

Corned answer = B. The anxiolytic properties of benzodiazepines, such as lorazepam, make them the drugs of choice in treating the anxiety and agitation of cocaine withdrawal. Lorazepam also has hypnotic properties. Phenobaibital has hypnotic properties but if s anxiolytic properties are inferior to those of the benzodiazepines. Cocaine itself could countered the agitation of withdrawal but its use would not be proper therapy. Hydroxyzine, an antihistaminic, is effective as an hypnotic and is sometimes used to deal with anxiety especially if emesis is a problem. Fluoxetine is an antidepressant with no immediate effects on anxiety. 

One of the problems associated with benzodiazepine anxiolytics is rebound anxiety and/or insomnia, which may occur between dose intervals or after withdrawal of the drug [83, 84], In three experiments performed with squirrel monkeys, (92) (up to 20 mg/kg p.o.) did not cause any apparent physical or behavioural signs of withdrawal after abrupt discontinuation of treatment or even after attempted precipitation of withdrawal by administration of flumazenil. 

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