Typical antipsychotics

Typical antipsychotics (sometimes referred to as first generation antipsychotics, conventional antipsychotics, classical neuroleptics, traditional antipsychotics, or major tranquilizers) are a class of antipsychotic drugs first developed in the 1950s and used to treat psychosis (in particular, schizophrenia). Typical antipsychotics may also be used for the treatment of acute mania, agitation, and other conditions. The first typical antipsychotics to come into medical use were the phenothiazines, namely chlorpromazine which was discovered serendipitously. Another prominent grouping of antipsychotics are the butyrophenones, an example of which would be haloperidol. The newer, second-generation antipsychotics, also known as atypical antipsychotics, have replaced the typical antipsychotics due to the Parkinson-like side effects typicals have.

Both generations of medication tend to block receptors in the brain's dopamine pathways, but atypicals at the time of marketing were claimed to differ from typical antipsychotics in that they are less likely to cause extrapyramidal motor control disabilities in patients, which include unsteady Parkinson's disease-type movements, body rigidity and involuntary tremors. More recent research has demonstrated the side effect profile of these drugs is similar to older drugs, causing the leading medical journal The Lancet to write in its editorial "the time has come to abandon the terms first-generation and second-generation antipsychotics, as they do not merit this distinction." These abnormal body movements can become permanent even after medication is stopped. While typical antipsychotics are more likely to cause parkinsonism, atypicals are more likely to cause weight gain and type II diabetes.

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