Why is quetiapine (Seroquel, Seroquel XR) prescribed to patients?

• Seroquel or Seroquel XR is used alone or in combination with other drugs to treat schizophrenia and bipolar disorder. It also is used for treating major depression in combination with antidepressants.

What are the side effects of quetiapine (Seroquel, Seroquel XR)?

What are the side effects of quetiapine (Seroquel, Seroquel XR)?

• The most common side effects of Seroquel or Seroquel XR are
  • headache,
  • agitation,
  • dizziness,
  • drowsiness,
  • weight gain, and
  • and stomach upset.
• Possible serious side effects include
  • suicidality,
  • worsening of depression,
  • extrapyramidal symptoms,
  • tarkive dykinesia,
  • serious allergic reactions,
  • seizures,
  • stroke, and
  • priapism.
• Other important side effects include a potentially fatal complex referred to as neuroleptic malignant syndrome (NMS), in which patients may have
  • high fevers,
  • muscle rigidity,
  • altered mental status,
  • irregular pulse or blood pressure,
  • rapid heart rate,
  • excessive sweating, and
  • heart arrhythmias.
• Quetiapine frequently causes tiredness (1 in 5 patients), especially during the first 3-5 days of treatment. Because of this tiredness, care should be exercised in any activity requiring mental alertness such as operating a motor vehicle or hazardous machinery.
• Less common side effects include seizures (1 in 125 patients) and hypothyroidism (1 in 250 patients).

Warning for people with high or low blood pressure and Seroquel or Seroquel XR

• Seroquel or Seroquel XR can cause orthostatic hypotension (a drop in blood pressure upon standing that can lead to dizziness or fainting) especially during the first 3-5 day period of treatment, when it is restarted after temporary discontinuation, and after an increase in the dose. The risk of orthostatic hypotension is about 1 in 100 (one of every hundred patients who take quetiapine).

• As with other antipsychotics, long-term use of quetiapine may lead to irreversible tardive dyskinesia, a neurologic disease which consists of involuntary movements of the jaw, lips, and tongue.

Warning for people with cataracts taking Seroquel or Seroquel XR

• In animals, quetiapine has been associated with the development of cataracts, and cataracts have been reported in patients using quetiapine for prolonged periods. Although it is not clear if quetiapine was responsible for the cataracts seen in humans, eye examinations by slit-lamp (to identify cataracts before they impair vision) are recommended at the beginning of treatment and every six months during treatment. If cataracts form, treatment should be discontinued.

Warning for people with high triglycerides or cholesterol taking Seroquel or Seroquel XR

• Quetiapine may increase blood concentrations of cholesterol and triglycerides by 11% and 17%, respectively.

Warning for people with diabetes taking quetiapine taking Seroquel or Seroquel XR

• There is an increased risk of hyperglycemia (high blood glucose) and diabetes-related events in patients taking atypical antipsychotics, including quetiapine. Patients should be tested during treatment for elevated blood-sugars. Additionally, persons with risk factors for diabetes, including obesity or a family history of diabetes, should have their fasting levels of blood sugar tested before starting treatment and periodically throughout treatment to detect the onset of diabetes. Any patient developing symptoms that suggest diabetes during treatment should be tested for diabetes.

Quick GuideSchizophrenia: Symptoms, Types, Causes, Treatment

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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.