Dystonia antipsychotic drugs

The answer is c. (Hardman, pp 414-4163) Unwanted pharmacologic side effects produced by phenothiazine antipsychotic drugs (e.g., perphenazine) include Parkinson-like syndrome, akathisia, dystonias, galactorrhea, amenorrhea, and infertility. These side effects are due to the ability of these agents to block dopamine receptors. The phenothiazines also block muscarinic and a-adrenergic receptors, which are responsible for other effects. 

Unfortunately, these drugs—especially the first generation of antipsychotics introduced in the 1950s—have side effects similar to those seen in patients with Parkinson s disease tremors when at rest, reduction of voluntary movement, muscle spasticity and dystonia, or sustained muscle contractions. These symptoms confirm the role of dopamine neurons in the initiation and control of movement. Antipsychotic drugs also block dopamine receptors within a region of the brain that controls... 

Burke, R., Fahn, S., Jankovic, J., Marsden, C. D., Lang, A. E., Gollomp, S., et al. (1982). Tardive dystonia Late-onset and persistent dystonia caused by antipsychotic drugs. 

Acute dystonia is a recognized complication of treatment with antipsychotic drugs and it can also occur with SSRIs and the anxiolytic drug buspirone. 

Christodoulou C, Kalaitzi C. Antipsychotic drug-induced acute laryngeal dystonia two case reports and a mini review. J Psychopharmacol 2005 19 307-12. 

Burke RE, Fahn S, Jankovic J, Marsden CD, Lang AE, Gollomp S, Ilson J. Tardive dystonia late-onset and persistent dystonia caused by antipsychotic drugs. Neurology 1982 32(12) 1335-46. 

Two patients with schizophrenia who developed focal tardive dystonia with atypical antipsychotic drugs (risperidone and olanzapine) had marked sustained improvement when quetiapine was gradually introduced and the other antipsychotic drugs were withdrawn there was no loss of control of psychotic symptoms (10). 

A variety of neurologic syndromes, involving particularly the extrapyramidal system, occur following short- or long-term use of neuroleptic (antipsychotic) drugs. These include akathisia, dystonia, neuroleptic malignant syndrome, parkinsonism, and tardive dyskinesia. 

Figure 29-1. Reiative extrapyramidai and autonomic toxicities of representative antipsychotic drugs. Ex-trapyramidai toxicities take the form of parkinsonism, akathisias, and dystonias. Autonomic toxicities are manifested as aipha-adrenoceptor blockade (orthostatic hypotension) or muscarinic blockade (dry mouth, blurred vision, urinary retention).

In human medicine, chlorpromazine is used mainly as a sedative, tranquilizer and antipsychotic drug. It is widely regarded as a safe drug but it can produce side-effects, some of them severe. Many of these effects are due to its anticholinergic effects and include slurred speech, dry mouth, constipation, urinary retention, dystonia, tardive dyskinesia and akathisia. It can also, rarely. 

Antipsychotics are a chemically diverse group of drugs having in common the ability to ameliorate psychotic symptoms. Unfortunately, a significant percentage of patients fail to respond adequately or may develop adverse effects such as acute EPS, various tardive syndromes (e.g., TD, dystonia, etc.), and, less commonly, even more serious adverse events such as NMS and agranulocytosis. 

Raja M. Managing antipsychotic-induced acute and tardive dystonia. Drug Saf 1998 19(l) 57-72. 

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