The most disturbing and common side effects of typical antipsychotic drugs are those effects known as extrapyramidal symptoms, which involve the nerves and muscles controlling movement and coordination. Women are at higher risk for these symptoms, and the risk increases with length of therapy and age. A condition known as acute dystonia can develop shortly after taking antipsychotic drugs. This syndrome includes abnormal muscle spasms, particularly sustained contortions of the neck, jaw, trunk, and eye muscles. The most serious effect of antipsychotic therapy is tardive dyskinesia , which is often manifest by repetitive and involuntary movements, or tics, most often of the mouth, lips, or of the legs, arms, or trunk.
Symptoms range from mild to severe, and sometimes interfere with eating and walking.
They can appear months or even years after taking the drugs. After the drug is withdrawn, symptoms can sometimes persist for weeks or months. Some cases of tardive dyskinesia may be permanent although they can go into remission, or remit completely. Treatment of Extrapyramidal Side Effects. Some of these drugs may also be helpful in managing negative symptoms of schizophrenia.