Antipsychotic agents sedation

Pharmacology The tricyclic antidepressants (TCAs), structurally related to the phenothiazine antipsychotic agents, possess 3 major pharmacologic actions in varying degrees Blocking of the amine pump, sedation, and peripheral and central... 

Antipsychotic agent Approx. equiv. dose (mg) Usual oral adult daily dose range (mg) Sedation EPS Anticholinergic effects ... 

The impact of antipsychotic agents on consciousness is immediately apparent from the frequency with which sedation and drowsiness are reported as side effects (Tune et ah, 1991), a property which historically has been used as a treat-... 

Three subfamilies of phenothiazines, based primarily on the side chain of the molecule, were once the most widely used of the antipsychotic agents. Aliphatic derivatives (eg, chlorpromazine ) and piperidine derivatives (eg, thioridazine ) are the least potent. These drugs produce more sedation and weight gain. Piperazine derivatives are more potent (effective in lower doses) but not necessarily more efficacious. Perphenazine, a piperazine derivative, was the typical antipsychotic drug used in the CATIE study described in the following text. The piperazine derivatives are also more selective in their pharmacologic effects (Table 29-1). 

Hyoscine and sedating antihistamines increase the effects of other drugs that cause sedation or have antimuscarinic actions, including many antidepressants and antipsychotic agents. 

I Sedation and Cognition. Sedation must be recognized as an antipsychotic side effect and not as an indication of therapeutic effect. It occurs more frequently with antipsychotics with antihistaminic properties. Chlorpromazine, thioridazine, mesoridazine, clozapine, olanzapine, and quetiapine are most frequently implicated. Administration of most or all of the daily dosage at bedtime (depending on the drug half-life) can decrease daytime sedation and in some patients eliminate the need for hypnotic agents. Sedation occurs early in treatment... 

Many of the side effects associated with antipsychotic agents can be attributed to their antagonist activity at a variety of CNS receptors, which include histamine Hi, adrenergic 01/02, cholinergic Mi receptors, serotonin 5-HT2, and dopamine D2 receptors in the brain. For example, antipsychotic drug side effects such as sedation. 

Which of the following agents possesses pharmacological actions characterized by high antipsychotic potency, high potential for extrapyramidal toxicity, and a low likelihood of causing sedation ... 

Buspirone may be an effective anxiolytic in the elderly patient and less likely than BZDs to produce excessive sedation ( 352, 353, 354 and 355). Dizziness, however, may be a problem. Zolpidem or zaleplon, particularly in lower doses (i.e., 2.5 to 5.0 mg at bedtime) may be viable alternatives ( 356). The elimination half-life of these two agents is approximately 3 hours in the elderly. Although it has sleep-enhancing properties similar to BZD hypnotics, it is less likely to alter sleep architecture. Whereas antidepressants and b -blockers may be useful alternatives in younger patients, no data document their effectiveness for anxiety in elderly patients ( 307). Although antipsychotics may be helpful in reducing severe agitation, their side effect profile makes them unsuitable for use in subjective anxiety states ( 300, 307). 

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