Psychotropic agents tricyclic antidepressants

Gastric acidity will also affect the absorption of medication. An acidic environment increases the absorption of weak acids, whereas the absorption of weak bases is facilitated by a less acidic environment. Many psychotropic agents such as tricyclic antidepressants (TCAs] and benzodiazepines are weak bases. Older studies of gastric acid secretion found that women have approximately 33%-40% lower basal gastric acid secretion than do men [Yonkers and Hamilton 1995]. Gastric acid secretion may be further decreased in the luteal phase of the menstrual cycle (Booth et al. 1957]. 

The initial clinical review should include a search for known consequences of poisoning, which include impaired consciousness with flacddity (benzodiazepines, alcohol, trichloroethanol) or with hypertonia (tricyclic antidepressants, antimuscaiinic agents), hypotension, shock, cardiac arrhythmia, evidence of convulsions, behavioural disturbances (psychotropic drugs), hypothermia, aspiration pneumonia and cutaneous blisters, burns in the mouth (corrosives). 

Uremia Antihistamines Antiparkinsonian agents Antispasmodics Ophthalmic preparations OTC sleep/allergy medications Tricyclic antidepressants Other medications Analgesics/NS AIDs Anticonvulsants Corticosteroids (high dose) Digoxin H2 blockers Insulin Muscle relaxants Narcotics Psychotropics (anxiolytic, antidepressant, antipsychotic) Sedative/hypnotic Sulfonylurea... 

Important biological differences that potentially affect the metabolism of psychotropics have been described between Japanese and non-Asian children. For example, a pharmacogenetic ethnic difference was reported in cytochrome P450 (CYP) 2D6 metabolism of several antipsychotics and antidepressants, and in the CYP 2C19 metabolism of tricyclic agents. In adults, the rate of poor metabolizers of CYP 2D6 substrates is lower in Asians (about 1%) than in Caucasians (about 7%), while that of CYP 2C19 substrates is higher in Asians (15%-30%) than in Caucasians (3%-6%) (Poolsup et ah, 2000). Clinicians may need to keep these differences in mind when they use psychotropics in Japanese and other Asian patients, since such differences can lead to different behavioral responses or toxicity. 

The first psychotropics of the modern era (e.g., lithium, neuroleptic antipsychotics, tricyclic and monoamine oxidase inhibitor antidepressants) were discovered serendipitously. These agents were not engineered to have selective actions, but instead produce a wide range of central biochemical effects and generally affect more than one neurotransmitter system simultaneously, resulting in multiple repercussions ... 

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