Other Antianxiety Drugs

Buspirone causes less additive CNS depression than do the other antianxiety drugs. However, it is recommended that concurrent use with a CNS depressant be avoided. Buspirone may increase serum digoxin levels, which increases the risk of digitalis toxicity. 

Since the early 1960s, the BZDs have accounted for more than half the total world sales of tranquilizers. As of 2002, the BZDs were the most commonly prescribed class of tranquilizers in the United States. According to FDA data, however, there has been a dramatic decline in the use of minor tranquilizers and other antianxiety drugs since 1975, when prescriptions peaked at 103 million. An American Psychiatric Association task force report estimates that annual prescriptions for BZDs have leveled off since the mid-1980s to about 61 million. 

Some antianxiety drug, such as buspirone (BuSpar), seem to have less abuse potential and less effect on motor ability and cognition than that of Hie other anfianxiety drug. 

Preanesthetic drugs may be omitted in those 60 years or older because many of the medical disorders for which these drugsare contraindicated are seen in older individuals For example, atropine and glycopyrrolate, drugs that can be used to decrease secretions of the upper respiratory tract, are contraindicated in certain medical disorders such as prostatic hypertrophy, glaucoma, and myocardial ischemia. Other preanesthetic drugs that depress the central nervous astern (CN, such as narcotics barbiturates and antianxiety drugs with or without antiemetic properties may be contraindicated in the older individual. 

In summary, buspirone is an effective generalized anxiety treatment that differs from conventional antianxiety drugs in speed of symptom reduction and types of symptoms affected. Although buspirone might seem to be the drug of choice for treatment of chronic anxiety, it has not displaced the use of benzodiazepines in the treatment of anxiety, perhaps because of its side-effect profile [dizziness, sedation, nausea], slow onset of action, and the opinion of some clinicians that its anxiolytic efficacy is less robust than that of benzodiazepines. Buspirone is accepted as an anxiolytic treatment much more widely in the United States than in most other countries [Kunovac and Stahl 1995]. 

Anxiety is a emotional feeling of fear along with discomfort and uneasiness. Antianxiety drugs are used to control the symptoms of anxiety without affecting the other mental and physical functions of the body. They are classified as in table 2.5.2. 

Schedule IV. These drugs supposedly have a lower potential for abuse than schedule III drugs, with only a limited possibility of physical dependence, psychologic dependence, or both. Examples include certain antianxiety drugs (meprobamate), certain barbiturates (barbital, phenobarbital), and a variety of other depressants and stimulants. 

The benzodiazepines are used primarily as sedative-antianxiety drugs (see Chapters 16 and 17) but also have broad antiseizure properties. Clonazepam (KLONOPIN) and clorazepate (TRANXENE-SD, others) have been approved in the U.S. for the long-term treatment of certain types of seizures. Diazepam (VAUUM, diastat others) and lorazepam (ativan) have well-defined roles in the management of status epilepticus. 

The antiemetics and antivertigo drug may have additive effects when used with alcohol and other CNS depressants such as sedatives, hypnotics, antianxiety drugp, opiates, and antidepressants. There may be additive anticholinergic effects (see Chap. 25) when administered with drag s that have anticholinergic activity such as the antihistamines, antidepressants, pheno-thiazines, and disopyramide The antacids decrease absorption of the antiemetics. 

From the examination of structure-activity relationships, it has been concluded that a phenyl moiety at C-6 as well as a 4-hydroxypiperidine side-chain attached to C-3 of the pyridazine system is essential for anticonvulsant activity in this class of compounds [184], Compounds (54) and (55) have been found to have similar anticonvulsant profiles in animals (mice, rats and baboons) [165, and literature cited therein] and to represent potent broad-spectrum antiepileptic drugs. Their potency with regard to antagonizing seizures (induced by electro-shock or various chemicals) has been compared with standard anticonvulsants like carbamazepine and phenobarbitone [185, 186], A quantitative electroencephalographic analysis of (55) has been published [187]. From in vitro studies it has been concluded that the anticonvulsant activities of these compounds are not mediated by an enhancement of GABAergic transmission or by an interaction with benzodiazepine receptor sites [ 165,186,187], On the other hand, in vivo experiments showed that (54), at anticonvulsant doses, increases the affinity of flunitrazepam for its central receptor site [ 186], Investigations of (54) and (55) in a behavioural test predictive of antianxiety activity revealed a marked difference in the pharmacological profiles of these structurally closely related compounds the dichloro compound SR 41378 (55) has also been found to possess anxiolytic (anticonflict) properties [165],... 

Other indications for the use of antipsychotics include Tourette s syndrome, disturbed behavior in patients with Alzheimer s disease, and, with antidepressants, psychotic depression. Antipsychotics are not indicated for the treatment of various withdrawal syndromes, eg, opioid withdrawal. In small doses, antipsychotic drugs have been promoted (wrongly) for the relief of anxiety associated with minor emotional disorders. The antianxiety sedatives (see Chapter 22) are preferred in terms of both safety and acceptability to patients. 

Other drugs of the depressant, antianxiety, antipyschotic, and anticonvulsive types are being investigated as treatments for cocaine abuse. Those which have been or will be covered in this course include the heterocyclic antidepressants desipramine and imipramine, which diminish cocaine use and craving as well as improve the outcome in the first few months of treatment. Buprenorphine (depressant) may augment the reward system (it has been found to suppress self-administration of cocaine in monkeys). Lithium sometimes works for those who are clinically depressives. Carbamazapine, bromocriptine and mazindol are also used as well as fluphenthixol and buspirone. 

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