Dosing and uses of Seroquel, Seroquel XR (quetiapine)
Adult dosage forms and strengths
tablet, immediate release
- 25mg
- 50mg
- 100mg
- 200mg
- 300mg
- 400mg
tablet, extended release
- 50mg
- 150mg
- 200mg
- 300mg
- 400mg
Schizophrenia
Immediate release
- Day 1: 50 mg/day PO divided q12hr
- Days 2-3: Dose increased daily in increments of 25-50 mg q8-12hr to 300-400 mg by day 4; further adjustments can be made in increments of 25-50 mg q12hr at intervals ≥2 days
- Dosage range: 150-750 mg/day
Extended release
- Day 1: 300 mg/day PO; subsequently, may be increased by up to 300 mg/day at intervals ≥1 day
- Maintenance (monotherapy): 400-800 mg/day
- Patients who have discontinued therapy for >1 week should have their dose retitrated following initiation of therapy; patients may reinitiate at their previous maintenance dose if discontinued therapy <1 week
Bipolar I Disorder, Mania
Administered as monotherapy or as adjunct to lithium or divalproex
Immediate release
- Day 1: 100 mg/day PO divided q12hr
- Day 2: 200 mg/day PO divided q12hr
- Day 3: 300 mg/day PO divided q12hr
- Day 4: 400 mg/day PO divided q12hr
- Further dosage adjustments, up to 800 mg/day by day 6, should be in increments ≤200 mg/day
- Dosage range: 400-800 mg/day; not to exceed 800 mg/day
Extended release
- Day 1: 300 mg PO once daily
- Day 2: 600 mg PO once daily
- Maintenance (day 3 onward): 400-800 mg/day PO
Bipolar Disorder, Depressive Episodes
Either immediate-release or extended-release tablets may be given; dosage titrated upward over 4 days
Day 1: 50 mg PO at bedtime
Day 2: 100 mg PO at bedtime
Day 3: 200 mg PO at bedtime
Maintenance (day 4 onward): 300 mg PO at bedtime
Bipolar I Disorder, Maintenance
Administered as adjunct to lithium or divalproex
Immediate release: 400-800 mg/day PO divided q12hr
Extended release: 400-800 mg/day PO in single dose
Generally, in maintenance phase, patients continue to receive same dosage on which they were stabilized
Major Depressive Disorder
Extended-release formulation administered as adjunct to antidepressants
Days 1 and 2: 50 mg PO in evening
Day 3: May be increased to 150 mg PO in evening
Dosage range: 150-300 mg/day
Alcohol Dependence (Off-label)
25-50 mg PO at bedtime; may be titrated; not to exceed 300 mg
Insomnia (Off-label)
Usually, 25 mg/day PO at bedtime initially
Administration
Preferably, take in evening without food or with light meaL
Switching from immediate release to extended release
- Convert to extended release tablets at equivalent immediate release total daily dose; administer once daily; individual adjustments may be necessary
Pediatric dosage forms and strengths
tablet, immediate release
- 25mg
- 50mg
- 100mg
- 200mg
- 300mg
- 400mg
tablet, extended release
- 50mg
- 150mg
- 200mg
- 300mg
- 400mg
Schizophrenia
<12 years
- Safety and efficacy not established
>12 years (monotherapy, immediate release)
- Day 1: 50 mg/day PO divided q12hr
- Day 2: 100 mg/day PO divided q12hr
- Day 3: 200 mg/day PO divided q12hr
- Day 4: 300 mg/day PO divided q12hr
- Day 5: 400 mg/day PO divided q12hr; further adjustments should be in increments ≤100 mg/day
- Dosage range: 400-800 mg/day
- Depending on response and tolerance, daily dose may be divided q8hr
>12 years (monotherapy, extended release)
- Day 1: 50 mg/day PO once daily
- Day 2: 100 mg/day PO once daily
- Day 3: 200 mg/day PO once daily
- Day 4: 300 mg/day PO once daily
- Day 5: 400 mg/day PO once daily; further adjustments should be in increments ≤100 mg/day
Bipolar I Disorder, Mania
<10 years
- Safety and efficacy not established
>10 years (monotherapy, immediate release)
- Day 1: 50 mg/day PO divided q12hr
- Day 2: 100 mg/day PO divided q12hr
- Day 3: 200 mg/day PO divided q12hr
- Day 4: 300 mg/day PO divided q12hr
- Day 5: 400 mg/day PO divided q12hr; further adjustments should be in increments ≤100 mg/day
- Dosage range: 400-600 mg/day
- Depending on response and tolerance, daily dose may be divided q8hr
>10 years (monotherapy, extended release)
- Day 1: 50 mg/day PO once daily
- Day 2: 100 mg/day PO once daily
- Day 3: 200 mg/day PO once daily
- Day 4: 300 mg/day PO once daily
- Day 5: 400 mg/day PO once daily; further adjustments should be in increments ≤100 mg/day
- Dosage range: 400-600 mg once daily
Geriatric dosage forms and strengths
Not approved for dementia-related psychosis, because of increased risk of cardiovascular or infectious related deaths (see Black box warnings)
Schizophrenia, Bipolar Disorder
Immediate release: 50-200 mg/day PO; may be increased by 25-50 mg/day
Extended release: 50 mg/day PO; may be increased by 50 mg/day
Psychosis, Agitation Related to Alzheimer Dementia (Off-label)
12.5-50 mg/day PO initially; may be gradually increased as tolerated; not to exceed 200-300 mg/day
Seroquel, Seroquel XR (quetiapine) adverse (side) effects
>10%
Dizziness (1-18%)
Fatigue (3-14%)
Extrapyramidal symptoms (1-13%)
Increased diastolic blood pressure (41%)
Increased triglycerides (8-22%)
Increased total cholesterol (7-18%)
Increased appetite (2-12%)
Constipation (6-11%)
Dry mouth (9-44%)
Headache (7-21)
Somnolence (18-57%)
1-10%
Abdominal pain (4-7%; dose related)
Dyspepsia (2-7%; dose related
Tremor (2-8%)
Back pain (3-5%)
Postural hypotension (2-7%)
Tachycardia (1-6%)
Pharyngitis (4-6%)
Rhinitis (3-4%)
Rash (4%)
Blurred vision (1-4%)
Arthralgia (1-4%)
Myalgia (2%)
Neck pain (2%)
Dyskinesia (4%)
Neutropenia (2%)
Hemorrhage (1%)
< 1%
Priapism
Cardiomyopathy, myocarditis
QTc prolongation
Night mares
Pancreatitis
Rhabdomyolysis
Palpitation
Leukocytosis
Epistaxis
Exfoliative dermatitis
Postmarketing Reports
Drug reaction with eosinophilia and systemic symptoms (DRESS)
Warnings
Black box warnings
Not approved for dementia-related psychosis; elderly patients with dementia-related psychosis who are treated with antipsychotic drugs are at increased risk of death, as shown in short-term controlled trials; deaths in these trials appeared to be either cardiovascular (eg, heart failure, sudden death) or infectious (eg, pneumonia) in nature
Increased risk of suicidal thinking and behavior in children, adolescents, and young adults taking antidepressants for major depressive disorder and other psychiatric disorders; prescriptions should be written for smallest therapeutically effective quantity, and caregivers should monitor and report to healthcare professionals incidence of suicidality and associated behaviors
Not approved for children <10 years
Contraindications
Documented hypersensitivity
Cautions
Use with caution in cardiovascular and cerebrovascular disease
May worsen hypotensive conditions
Use with caution in breast cancer and history of seizure
Increased risk of hyperglycemia and diabetes; in some cases, hyperglycemia concomitant with use of atypical antipsychotics has been associated with ketoacidosis, hyperosmolar coma, or death; monitor blood glucose of high-risk patients for symptoms of hyperglycemia including polydipsia, polyuria, polyphagia, and weakness; monitor glucose regularly in patients with diabetes or at risk for diabetes
Increased incidence of cerebrovascular adverse effects, including stroke and TIAs, in elderly with dementia (not approved for the treatment of patients with dementia-related psychosis); see Black box warnings
Neuroleptic malignant syndrome (NMS) reported with use
Tardive dyskinesia possible after discontinuance
Clinical worsening of depression and suicide ideation may occur despite treatment
Hyperlipidemia may occur; appropriate clinical monitoring is recommended, including fasting blood lipid testing at the beginning of, and periodically, during treatment
Weight gain may occur; monitoring of weight recommended
Orthostatic hypotension associated with use
Monitor for cataract
Increased blood pressure in children and adolescents reported; monitor blood pressure at the beginning of, and periodically during treatment
Leukopenia, neutropenia, and agranulocytosis may occur
Somnolence may occur (especially with extended-release product)
Potential for withdrawal symptoms after abrupt discontinuance
False-positive urine drug screens reported when immunoassays for methadone or tricyclic antidepressants used
FDA warning regarding off-label use for dementia in elderly (see Black box warnings)
QT interval prolongation
- Not associated with persistent increase in QT interval in trials, but QT effect was not systematically evaluated in thorough study
- QT prolongation reported with acute overdose during postmarketing experience
- Avoid using in combination with other drugs known to prolong QTc or in patients with increased risk of QT prolongation
Pregnancy and lactation
Pregnancy category: C
Neonates exposed to antipsychotic drugs during 3rd trimester of pregnancy are at risk for extrapyramidal symptoms (EPS) or withdrawal symptoms after delivery; these complications vary in severity, with some being self-limited and others requiring ICU support and prolonged hospitalization
Lactation: Drug excreted in breast milk; breastfeeding not recommended
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Seroquel, Seroquel XR (quetiapine)
Mechanism of action
Atypical antipsychotic related to clozapine; reduces positive and negative symptoms of psychotic disorders via antagonism of multiple neurotransmitter receptors in brain, including dopamine D1 and D2, histamine H1, alpha1- and alpha2-adrenergic, and serotonin types 1 and 2 (5-HT1A, 5-HT2); has no affinity for benzodiazepine and cholinergic muscarinic receptors
Absorption
Bioavailability: 100%
Peak plasma time: Immediate release, 1.5 hr; extended release, 6 hr
Distribution
Protein bound: 83%
Vd: 6-14 L/kg
Metabolism
Metabolized in liver by CYP3A4
Elimination
Half-life: Immediate release, 6 hr; extended release, 7 hr
Excretion: Urine (73%), feces (20%)



