Thiothixene schizophrenia

Whatever the underlying causes may be, neuroleptic medications are the most effective treatment for schizophrenia. All antipsychotic medications have some form of dopamine receptor antagonism and they are distinguished by their chemical class. The phenothiazines include chlorpromazine (Thorazine), thioridazine (Mellaril), mesoridazine (Serentil), trifluoperazine (Stelazine), fluphenazine (Prolixin), and prochlorperazine (Compazine). The thioxanthenes include chlorprohixine (Taractan) and thiothixene (Navane). Butyrophenones are represented by haloperidol (Haldol). Loxapine (Loxitane) is a dibenzoxapine, and molindone (Moban) is a dihydroindolone. 

After dopamine was identified as a neurotransmitter in 1959, it was shown that its effects on electrical activity in central synapses and on production of the second messenger cAMP by adenylyl cyclase could be blocked by antipsychotic drugs such as chlorpromazine, haloperidol, and thiothixene. This evidence led to the conclusion in the early 1960s that these drugs should be considered dopamine-receptor antagonists and was responsible for the dopamine hypothesis of schizophrenia described earlier in this chapter. The antipsychotic action is now thought to be produced (at least in part) by their ability to block dopamine in the mesolimbic and mesocortical systems. 

Chlorpromazine Blockade of D2 receptors >> 5 2 receptors .-Receptor blockade (fluphenazine least) muscarinic (M)-receptor blockade (especially chlorpromazine and thioridazine) Hx-receptor blockade (chlorpromazine, thiothixene) t central nervous system (CNS) depression (sedation) t decreased seizure threshold t QT prolongation (thioridazine) Psychiatric schizophrenia (alleviate positive symptoms), bipolar disorder (manic phase) nonpsychiatric antiemesis, preoperative sedation (promethazine) pruritus Oral and parenteral forms, long half-lives with metabolism-dependent elimination Toxicity Extensions of effects on a - and M- receptors blockade of dopamine receptors may result in akathisia, dystonia, parkinsonian symptoms, tardivedyskinesia, and hyperprolactinemia... 

Huang CC, Gerhardstein RP, Kim DY, Hoiiister L. Treatment-resistant schizophrenia controiied study of moderate- and high-dose thiothixene, int Ciin Psychopharmacoi f 987 2 69-75. 

Thioxanthenes are used in the treatment of psychosis, including schizophrenia, senile psychosis, pathological jealousy, and borderline personality disorder. Other uses include the treatment of pain, postoperative neuralgia, sedation, anxiety neurosis, childhood behavior problems, and depression. The maximum therapeutic daily oral dose for chlorprothixene, flupenthixol, and thiothixene is 600, 224, and 60 mg respectively the maximum intramuscular dose of each is 200 mg day 100 mg weekly, and 30 mg dayrespectively. Some thioxanthenes and thioxanthenones have shown signs in mice and in vitro assays of possible human therapeutic potential against tumors, and some thioxanthenes have been shown to have cytotoxic and antimicrobial activities. 

Thiothixene, useful in treatment of schizophrenia, was also found useful in treating neurotic patients In another study, it was found as effective as the perphenazine-amitriptyline combination in treating psychoneurotic depressive symptoms4 ... 

The Food and Drug Administration approved New Drug Applications for use of butaperazine dimaleate, fluphenazine enanthate, haloperidol and thiothixene in treating schizophrenia. 

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