2.1 Important Administration Instructions
Quetiapine fumarate can be taken with or without food.
2.2 Recommended Dosing
The recommended initial dose, titration, dose range and maximum quetiapine fumarate dose for each approved indication is displayed in Table 1. After initial dosing, adjustments can be made upwards or downwards, if necessary, depending upon the clinical response and tolerability of the patient [see Clinical Studies (14.1 and 14.2)].
Table 1: Recommended Dosing for Quetiapine Fumarate
Indication
Initial Dose and Titration
Recommended Dose
Maximum Dose
Schizophrenia-Adults
Day 1: 25 mg twice daily. Increase in increments of 25 mg to 50 mg divided two or three times on Days 2 and 3 to range of 300 to 400 mg by Day 4. Further adjustments can be made in increments of 25 to 50 mg twice a day, in intervals of not less than 2 days.
150 to 750 mg/day
750 mg/day
Schizophrenia-Adolescents (13 to 17 years)
Day 1: 25 mg twice daily.
Day 2: Twice daily dosing totaling 100 mg.
Day 3: Twice daily dosing totaling 200 mg.
Day 4: Twice daily dosing totaling 300 mg.
Day 5: Twice daily dosing totaling 400 mg.
Further adjustments should be in increments no greater than 100 mg/day within the recommended dose range of 400 to 800 mg/day.
Based on response and tolerability, may be administered three times daily.
400 to 800 mg/day
800 mg/day
Schizophrenia-Maintenance
N/A1
400 to 800 mg/day
800 mg/day
Bipolar Mania-Adults Monotherapy or as an adjunct to lithium or divalproex
Day 1: Twice daily dosing totaling 100 mg.
Day 2: Twice daily dosing totaling 200 mg.
Day 3: Twice daily dosing totaling300 mg.
Day 4: Twice daily dosing totaling 400 mg.
Further dosage adjustments up to 800 mg/day by Day 6 should be in increments of no greater than 200 mg/day.
400 to 800 mg/day
800 mg/day
Bipolar Mania-Children and Adolescents (10 to 17 years), Monotherapy
Day 1: 25 mg twice daily.
Day 2: Twice daily dosing totaling 100 mg.
Day 3: Twice daily dosing totaling 200 mg.
Day 4: Twice daily dosing totaling 300 mg.
Day 5: Twice daily dosing totaling 400 mg.
Further adjustments should be in increments no greater than 100 mg/day within the recommended dose range of 400 to 600 mg/day. Based on response and tolerability, may be administered three times daily.
400 to 600 mg/day
600 mg/day
Bipolar Depression-Adults
Administer once daily at bedtime.
Day 1: 50 mg
Day 2: 100 mg
Day 3: 200 mg
Day 4: 300 mg
300 mg/day
300 mg/day
Bipolar I Disorder Maintenance Therapy-Adults
Administer twice daily totaling 400 to 800 mg/day as adjunct to lithium or divalproex. Generally, in the maintenance phase, patients continued on the same dose on which they were stabilized.
400 to 800 mg/day
800 mg/day
1 N/A Not applicable
Maintenance Treatment for Schizophrenia and Bipolar I Disorder
Maintenance Treatment – Patients should be periodically reassessed to determine the need for maintenance treatment and the appropriate dose for such treatment [see Clinical Studies (14.2)].
2.3 Dose Modifications in Elderly Patients
Consideration should be given to a slower rate of dose titration and a lower target dose in the elderly and in patients who are debilitated or who have a predisposition to hypotensive reactions [see Clinical Pharmacology (12.3)]. When indicated, dose escalation should be performed with caution in these patients.
Elderly patients should be started on quetiapine fumarate 50 mg/day and the dose can be increased in increments of 50 mg/day depending on the clinical response and tolerability of the individual patient.
2.4 Dose Modifications in Hepatically Impaired Patients
Patients with hepatic impairment should be started on 25 mg/day. The dose should be increased daily in increments of 25 mg/day to 50 mg/day to an effective dose, depending on the clinical response and tolerability of the patient.
2.5 Dose Modifications when used with CYP3A4 Inhibitors
Quetiapine fumarate dose should be reduced to one sixth of original dose when co-medicated with a potent CYP3A4 inhibitor (e.g., ketoconazole, itraconazole, indinavir, ritonavir, nefazodone, etc.). When the CYP3A4 inhibitor is discontinued, the dose of quetiapine fumarate should be increased by 6 fold [see Clinical Pharmacology (12.3) and Drug Interactions (7.1)].
2.6 Dose Modifications when used with CYP3A4 Inducers
Quetiapine fumarate dose should be increased up to 5 fold of the original dose when used in combination with a chronic treatment (e.g., greater than 7 to 14 days) of a potent CYP3A4 inducer (e.g., phenytoin, carbamazepine, rifampin, avasimibe, St. John’s wort etc.). The dose should be titrated based on the clinical response and tolerability of the individual patient. When the CYP3A4 inducer is discontinued, the dose of quetiapine fumarate should be reduced to the original level within 7 to 14 days [see Clinical Pharmacology (12.3) and Drug Interactions (7.1)].
2.7 Reinitiation of Treatment in Patients Previously Discontinued
Although there are no data to specifically address re-initiation of treatment, it is recommended that when restarting therapy of patients who have been off quetiapine fumarate for more than one week, the initial dosing schedule should be followed. When restarting patients who have been off quetiapine fumarate for less than one week, gradual dose escalation may not be required and the maintenance dose may be reinitiated.
2.8 Switching from Antipsychotics
There are no systematically collected data to specifically address switching patients with schizophrenia from antipsychotics to quetiapine fumarate, or concerning concomitant administration with antipsychotics. While immediate discontinuation of the previous antipsychotic treatment may be acceptable for some patients with schizophrenia, more gradual discontinuation may be most appropriate for others. In all cases, the period of overlapping antipsychotic administration should be minimized. When switching patients with schizophrenia from depot antipsychotics, if medically appropriate, initiate quetiapine fumarate therapy in place of the next scheduled injection. The need for continuing existing EPS medication should be re-evaluated periodically.