Seroquel XR Quetiapine Fumarate Extended-Release Tablets

1. Indications and Usage
Schizophrenia: Treatment of schizophrenia in adults and pediatric patients 13 to 17 years of age.
Bipolar Disorder:
Bipolar I Depression: Treatment of depressive episodes associated with Bipolar I Disorder (monotherapy).
Bipolar Mania: Treatment of manic episodes associated with Bipolar I Disorder (monotherapy or adjunctive with lithium or divalproex).
Maintenance Treatment: Adjunctive maintenance treatment in Bipolar I Disorder.
Major Depressive Disorder (MDD): Treatment of major depressive disorder as adjunctive therapy to antidepressants in adults.
2. Dosage and Administration
Route of Administration:
For Oral Use ONLY.
Recommended Dosage:
Schizophrenia:
Starting Dose: 50 mg once daily at bedtime.
Titration: Increase by 50–100 mg/day to target dose of 400–800 mg/day.
Bipolar Depression:
Starting Dose: 50 mg once daily at bedtime.
Target Dose: 300 mg once daily at bedtime.
Bipolar Mania:
Starting Dose: 100 mg once daily at daytime or bedtime.
Target Dose: 400–800 mg/day.
Adjunctive MDD:
Starting Dose: 50 mg once daily at bedtime.
Target Dose: 150–300 mg once daily at bedtime.
Critical Administration Instruction:
MUST BE SWALLOWED WHOLE: Do not chew, crush, or split the tablets.
Administration: Take once daily, either before bedtime or with a light meal.
3. Mechanism of Action
Receptor Profile:
Quetiapine is an atypical antipsychotic that binds to multiple neurotransmitter receptors in the brain.
Agonist/Antagonist Activity:
Antagonist: Acts as an antagonist at Serotonin (5-HT2A) and Dopamine (D2) receptors.
Partial Agonist: Acts as a partial agonist at Serotonin (5-HT1A) receptors.
Antagonist: Has high affinity for Histamine (H1) and Alpha-1 adrenergic receptors (contributing to sedative and hypotensive side effects).
4. Safety and Warnings
Increased Mortality in Elderly with Dementia (Boxed Warning):
Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death.
Suicidal Thoughts and Behaviors:
Monitor for the emergence of suicidal ideation and behavior.
Metabolic Changes:
Hyperglycemia, diabetes mellitus, dyslipidemia, and weight gain have occurred during treatment. Monitor blood glucose and lipids.
Orthostatic Hypotension:
Can cause a drop in blood pressure upon standing, leading to syncope (fainting).
Cataracts:
Associated with cataract development in animal studies; monitoring is recommended during initiation.
5.Adverse Reactions
Most Common:
Somnolence, dizziness, dry mouth, constipation, increased appetite, fatigue, weight gain, and dyspepsia.
6.Drug Interactions
CYP3A4 Substrate:
Quetiapine is primarily metabolized by CYP3A4.
Strong CYP3A4 Inhibitors:
Contraindicated (e.g., ketoconazole, itraconazole, grapefruit juice) as they significantly increase quetiapine levels.
Strong CYP3A4 Inducers:
Contraindicated (e.g., phenytoin, carbamazepine, rifampin) as they significantly decrease quetiapine levels.
7.Pharmaceutical Information
Chemical Composition:
Active Ingredient: Quetiapine Fumarate.
Available Strength: 50 mg, 150 mg, 200 mg, 300 mg, 400 mg tablets.
Appearance: Film-coated, capsule-shaped tablets.
Storage: Store at 25°C (77°F); excursions permitted to 15–30°C (59–86°F).