Antipsychotic drugs essential

Although the traditional neuroleptics do not bind to serotonin (5-MT) receptors with significant affinity, all of the atypical antipsychotics do. This observation has led to the hypothesis that 5-HT receptor blockade is an essential feature of the atypical antipsychotic drugs... 

Many of the naturally occurring tricyclic thiazines are essentially naphtho analogues of the benzothiazines discussed in the previous section, and are isolated mainly from bacterial or marine sources, although the best-known tricyclic thiazine is the phenothiazine chlorpromazine. This compound, 2-chloro-l 0-(3-dimethylaminopropyl)phenothiazine developed in the early 1950s was one of the first antipsychotic drugs on the market, and although it is claimed to be a natural product (03MI05), the evidence is extremely weak, and therefore it is not included here. 

Essentially all antipsychotic medications pass through the placenta. The use of these drugs requires critical attention to the timing of the exposure, the dose and duration of use, and fetal susceptibility. When possible, discontinuing antipsychotics for the first trimester is the safest option, as weeks 6 to 10 are the most vulnerable period for organ formation. 

Another use of the laboratory is for therapeutic drug monitoring (TDM) of psychotropics with defined optimal ranges, narrow therapeutic indices, or both. Although TDM is not essential for many psychotropics, it is for others, including lithium, several TCAs, valproate, and carbamazepine. It may also be helpful to optimize the use of certain antipsychotics (e.g., haloperidol, clozapine) ( 7). 

Similar examples abound in most fields of therapeutics. For example, the major tranquilizer chlor-promazine—the first drug found to have true antipsychotic properties—is a trivial modification of phenothiazine, which was known for decades and used as a de-wormer for livestock. The parent phenothiazine, and many of its structural modifications, have no antipsychotic activity at all it is only certain minor structural modifications that have the essential pharmacologic and therapeutic properties. (Chlorpromazine also happens to be a classic example of the serendipitous empirical-clinical method of discovery of a drug s unique therapeutic value, a method described below.)... 

The first generation antipsychotics, now known as typical drugs, were all D2 receptor blockers and, as such, very likely to produce Parkinsonian side effects. Because antipsychotic potency was associated with D2 receptor affinity, it was assumed that dopamine overactivity was the essential defect in schizophrenia and that a direct dopamine blockade was the definitive route to treatment. But these drugs affected both the target dopamine pathways of the mesolimbic projection and the uninvolved nigrostriatal projection. Unfortunately, that meant that movement disorders were the price that had to be paid for antipsychosis. 

Stahl s Essential Psychopharmacology has established itself as the preeminent source of education and information in its field. This much expanded second edition enlists advances in neurobiology and recent clinical developments to explain with renewed clarity the concepts underlying drug treatment of psychiatric disorders. New neurotransmitter systems, new theories of schizophrenia, clinical advances in antipsychotic and antidepressant therapy, new coverage of attention deficit disorder, sleep disorders, and drug abuse, and a new chapter on sex-specific and sexual function-related psychopharmacology—these are all features of this edition. 

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