THERAPEUTICS

Brands

• Seroquel, Ketipinor, Seroquel XR

Generic?

• Yes

Class

• Atypical antipsychotic

Commonly Prescribed for

(FDA approved in bold)

• Schizophrenia

• Bipolar disorder (depression and mania) as monotherapy or adjunct to lithium and divalproex

• Adjunctive therapy for major depressive disorder (extended-release only)

• Psychosis associated with Parkinson’s disease (PD) or dementia with Lewy bodies (DLB)

• Augmentation for refractory obsessivecompulsive disorder

• Autism

• Alcoholism

• Gilles de la Tourette syndrome (GTS)

• Insomnia

• Anxiety

How the Drug Works

• A benzothiazepine derivative. At lower dose, quetiapine is H1,2 and α1-adrenergic blocker. At higher dose, quetiapine starts blocking more D2,3 (as other neuroleptics) and 5-HT2A receptors

• Lower D2/3 binding constant than haloperidol reduces its risk of motor side effects

• Binding to other receptors may improve depression and cognitive problems

How Long Until It Works

• Schizophrenia/bipolar: may be effective in days, more commonly takes weeks or months to determine best dose and achieve best clinical effect. Usually 4–6 weeks

• Insomnia: may be effective immediately

If It Works

• Continue to use at lowest required dose. Most patients with schizophrenia see a reduction in psychosis with quetiapine (and other neuroleptics), but some patients, including many with PD and DLB, may improve more than 50%

If It Doesn't Work

• Increase dose

• In psychosis related to PD or DLB, reduce dose or eliminate offending medications, such as dopamine agonists or amantadine

• If not effective consider changing to clozapine. In PD and DLB, avoid long-term use of conventional antipsychotics

• Insomnia: if no sedation occurs despite adequate dosing, change to another agent

Best Augmenting Combos for Partial Response or Treatment-Resistance

• Patients with affective disorders, such as bipolar disorder, may respond to moodstabilizing AEDs, lithium, or benzodiazepines. In PD and DLB, cholinesterase inhibitors may improve symptoms (particularly in DLB)

Tests

• Prior to starting treatment and periodically during treatment, monitor weight, blood pressure, lipids, and fasting glucose due to risk of metabolic syndrome