Side Effects of the Medications Used to Treat Schizophrenia

In-depth look at the major side effects of antipsychotic medications.

In-depth look at the major side effects of antipsychotic medications.

All medications have side effects. Different medications produce different side effects, and people differ in the amount and severity of side effects they experience. Side effects of antipsychotic medications can often be treated by changing the dose of the medication, switching to a different medication, or treating the side effect directly with an additional medication.

Common inconvenient side effects of all antipsychotic drugs used to treat schizophrenia include:

  • dry mouth
  • constipation
  • blurred vision
  • drowsiness

Some people experience sexual dysfunction or decreased sexual desire and menstrual changes.

Atypical Antipsychotics Linked to Diabetes

One of the most frequent complaints about atypical antipsychotics is that they induce significant weight gain. Because atypical antipsychotic drugs may increase the risk of obesity, diabetes, and high cholesterol, the FDA told makers of the drugs to include these risks in product labels.

Other common side effects relate to muscles and movement problems. These side effects include restlessness, stiffness, tremors, muscle spasms, and one of the most unpleasant and serious side effects, a condition called tardive dyskinesia.

  • Tardive Dyskinesia is a movement disorder where there are uncontrolled facial movements and sometimes jerking or twisting movements of other body parts. This condition usually develops after several years of taking antipsychotic medications and more predominantly in older adults. Tardive dyskinesia affects 15 to 20 percent of people taking conventional antipsychotic medications. The risk of developing tardive dyskinesia is lower for people taking the newer antipsychotics. Tardive dyskinesia can be treated with additional medications or by lowering the dosage of the antipsychotic if possible. The symptoms of TD may persist even after the medication is discontinued.

  • Low White Blood Cell Count (Agranulocytosis)
    Clozapine (Clozaril) was the first atypical antipsychotic in the United States and seems to be one of the most effective medications, particularly for people who have not responded well to other medications. However, in some people, it has a serious side effect of lowering the number of white blood cells produced. People taking clozapine must have their blood monitored every one or two weeks to count the number of white blood cells in the bloodstream. For this reason, clozapine is usually the last atypical antipsychotic prescribed and is usually used as a last line treatment for people that do not respond well to other medications or have frequent relapses.

  • Neuroleptic Malignant Syndrome
    This is a rare, but very serious, side effect. Signs to watch for are muscle stiffness that occurs over one to three days, a high fever, and confusion. If these symptoms occur, seek medical help immediately - take your relative to the emergency room if you cannot reach his doctor.

APA Reference
Gluck, S. (2007, March 7). Side Effects of the Medications Used to Treat Schizophrenia, HealthyPlace. Retrieved on 2024, June 16 from

Last Updated: June 11, 2019

Medically reviewed by Harry Croft, MD

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