What is Quetiapine (Seroquel)?

From the Guidelines

Quetiapine should be used at a suggested starting dose of 25 mg (immediate release) p.o. stat, with a reduction in dose for older patients and patients with hepatic impairment, as it is sedating and less likely to cause extrapyramidal symptoms (EPSEs) compared to other antipsychotics 1. When considering the use of quetiapine, it is essential to weigh the potential benefits against the risks, particularly in terms of morbidity, mortality, and quality of life. The medication is primarily used to treat schizophrenia, bipolar disorder, and as an add-on treatment for major depressive disorder.

• The typical dosage ranges from 25-800mg daily, depending on the condition being treated, with lower doses often used for sleep or anxiety and higher doses for psychotic disorders.
• Common side effects include sedation, dizziness, dry mouth, constipation, and weight gain.
• Quetiapine works by blocking multiple neurotransmitter receptors in the brain, particularly dopamine and serotonin receptors, which helps regulate mood, thinking, and behavior.
• Patients should be monitored for metabolic changes, including weight gain, blood sugar elevations, and lipid abnormalities during treatment. In comparison to other antipsychotics, quetiapine has a more favorable side effect profile, with a lower risk of EPSEs 1. However, it is crucial to consider the individual patient's needs and medical history when selecting an antipsychotic medication.
• For example, olanzapine may be more suitable for patients who require a medication with a lower risk of orthostatic hypotension, while risperidone may be preferred for patients who are at risk of developing tardive dyskinesia 1. Ultimately, the decision to use quetiapine should be based on a thorough evaluation of the patient's condition and a careful consideration of the potential benefits and risks, with a focus on minimizing morbidity, mortality, and improving quality of life.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Quetiapine Overview

• Quetiapine is an atypical antipsychotic used in the treatment of schizophrenia, bipolar disorder, and major depressive disorder 2, 3, 4.
• It is available in both immediate-release and extended-release formulations 2, 5.

Efficacy in Bipolar Depression

• Quetiapine has been shown to be effective in the treatment of bipolar depression, with significant improvements in depressive symptoms and global severity of illness scores 2.
• It has also been found to be effective in preventing the recurrence of mood events in patients with bipolar disorder 2.

Tolerability and Safety

• Quetiapine is generally well-tolerated, with most treatment-emergent adverse events being mild to moderate in severity 2, 5.
• Common adverse events include dry mouth, sedation, somnolence, dizziness, and constipation 2, 5.
• Quetiapine has been found to have a lower risk of extrapyramidal symptoms compared to other antipsychotics 3.

Dosage and Administration

• The recommended dose of quetiapine for the treatment of schizophrenia is 300-500 mg/day 3, 6.
• However, in clinical practice, doses higher than 750 mg/day are often used, with some patients receiving doses up to 2400 mg/day 6.
• The efficacy and safety of high-dose quetiapine have not been established in double-blind randomized clinical trials 6.

Off-Label Uses

• Quetiapine is often used off-label to treat other depressive and anxiety disorders, including generalized anxiety disorder and obsessive-compulsive disorder 4.
• There is preliminary evidence to support the use of quetiapine in these conditions, but further randomized controlled trials are needed to confirm its efficacy and tolerability 4.