Extrapyramidal side effects of antipsychotics

What it is

The extrapyramidal side effects of antipsychotics, especially first generation ones, are four: akathisia, acute dystonia, Parkinsonism, and tardive dyskinesia.

Causes and risk

They come from antipsychotic treatment, and the first generation drugs carry them most; typical antipsychotics such as haloperidol have significant side effects. Tardive dyskinesia is of gradual onset after prolonged therapy of more than 6 months. Lewy body dementia carries an increased sensitivity to the extrapyramidal side effects of antipsychotics, which sits among its characteristics with fluctuating levels of attention and alertness, Parkinsonism with rigidity and tremors, and visual hallucinations. Among the atypical antipsychotics, aripiprazole has the least adverse effects.

How it presents

• Acute dystonia: sudden, sustained contraction of the neck, mouth, tongue and eye muscles. It usually involves spasm of head and neck muscles, and protrusion of the tongue, upward gaze, torticollis and trismus are common manifestations.
• Akathisia: subjective restlessness and inability to sit still, felt as an uncomfortable sensation with a need to constantly move around, so that sitting still is possible for only a few minutes at a time.
• Parkinsonism: gradual-onset tremor, rigidity, bradykinesia.
• Tardive dyskinesia: gradual onset after prolonged therapy of more than 6 months, with dyskinesia of the mouth, face, trunk and extremities. Involuntary chewing and lip-smacking movements are the typical form, and they may begin to show when the antipsychotic dose is tapered down.