Risperidone

Risperidone is indicated for: - "Acute and maintenance treatment of schizophrenia" in adults and adolescents 13-17 years - "Short-term treatment of acute manic or mixed episodes associated with Bipolar I Disorder" in adults and children/adolescents 10-17 years, alone or with lithium/valproate - "Treatment of irritability associated with autistic disorder," including aggression, self-injury, and tantrums, in children and adolescents aged 5-16 years

2 DOSAGE AND ADMINISTRATION Table 1. Recommended Daily Dosage by Indication Initial Dose Titration (Increments) Target Dose Effective Dose Range Schizophrenia: adults (2.1) 2 mg 1 to 2 mg 4 to 8 mg 4 to 16 mg Schizophrenia: adolescents (2.2) 0.5 mg 0.5 to 1 mg 3 mg 1 to 6 mg Bipolar mania: adults (2.2) 2 to 3 mg 1 mg 1 to 6 mg 1 to 6 mg Bipolar mania: children and adolescents (2.2) 0.5 mg 0.5 to 1 mg 1 to 2.5 mg 1 to 6 mg Irritability in autistic disorder (2.3) 0.25 mg Can increase to 0.5 mg by Day 4: (body weight less than 20 kg) 0.5 mg Can increase to 1 mg by Day 4: (body weight greater than or equal to 20 kg) After Day 4, at intervals of > 2 weeks: 0.25 mg (body weight less than 20 kg) 0.5 mg (body weight greater than or equal to 20 kg) 0.5 mg: (body weight less than 20 kg) 1 mg: (body weight greater than or equal to 20 kg) 0.5 to 3 mg Severe Renal and Hepatic Impairment in Adults: use a lower starting dose of 0.5 mg twice daily. May increase to dosages above 1.5 mg twice daily at intervals of one week or longer. Recommended daily dosage: Initial Dose Target Dose Effective Dose Range Schizophrenia: adults (2.1) 2 mg 4 to 8 mg 4 to 16 mg Schiophrenia: adolescents (2.1) 0.5 mg 3 mg 1 to 6 mg Bipolar mania: adults (2.2) 2 to 3 mg 1 to 6 mg 1 to 6 mg Bipolar mania in children and adolescents (2.2) 0.5 mg 1 to 2.5 mg 1 to 6 mg Irritability associated with autistic disorder (2.3) 0.25 mg (Weight <20 kg) 0.5 mg (Weight ≥20 kg) 0.5 mg (<20 kg) 1 mg (≥20 kg) 0.5 to 3 mg Severe Renal or Hepatic Impairment in Adults: Use a lower starting dose of 0.5 mg twice daily. May increase to dosages above 1.5 mg twice daily at intervals of at least one week. (2.4) 2.1 Schizophrenia Adults Usual Initial Dose Risperidone can be administered once or twice daily. Initial dosing is 2 mg per day. May increase the dose at intervals of 24 hours or greater, in increments of 1 to 2 mg per day, as tolerated, to a recommended dose of 4 to 8 mg per day. In some patients, slower titration may be appropriate. Efficacy has been demonstrated in a range of 4 mg to 16 mg per day. However, doses above 6 mg per day for twice daily dosing were not demonstrated to be more efficacious than lower doses, were associated with more extrapyramidal symptoms and other adverse effects, and are generally not recommended. In a single study supporting once-daily dosing, the efficacy results were generally stronger for 8 mg than for 4 mg. The safety of doses above 16 mg per day has not been evaluated in clinical trials [see Clinical Studies ( 14.1 )]. Adolescents The initial dose is 0.5 mg once daily, administered as a single-daily dose in the morning or evening. The dose may be adjusted at intervals of 24 hours or greater, in increments of 0.5 mg or 1 mg per day, as tolerated, to a recommended dose of 3 mg per day. Although efficacy has been demonstrated in studies of adolescent patients with schizophrenia at doses between 1 mg to 6 mg per day, no additional benefit was observed above 3 mg per day, and higher doses were associated with more adverse events. Doses higher than 6 mg per day have not been studied. Patients experiencing persistent somnolence may benefit from administering half the daily dose twice daily. Maintenance Therapy While it is unknown how long a patient with schizophrenia should remain on risperidone, the effectiveness of risperidone 2 mg per day to 8 mg per day at delaying relapse was demonstrated in a controlled trial in adult patients who had been clinically stable for at least 4 weeks and were then followed for a period of 1 to 2 years [see Clinical Studies ( 14.1 )] . Both adult and adolescent patients who respond acutely should generally be maintained on their effective dose beyond the acute episode. Patients should be periodically reassessed to determine the need for maintenance treatment. Reinitiation of Treatment in Patients Previously Discontinued Although there are no data to specifically address reinitiation of treatment, it is recommended that after an interval off risperidone, the initial titration schedule should be followed. Switching From Other Antipsychotics There are no systematically collected data to specifically address switching schizophrenic patients from other antipsychotics to risperidone, or treating patients with concomitant antipsychotics. 2.2 Bipolar Mania Usual Dose Adults The initial dose range is 2 mg to 3 mg per day. The dose may be adjusted at intervals of 24 hours or greater, in increments of 1 mg per day. The effective dose range is 1 mg to 6 mg per day, as studied in the short-term, placebo-controlled trials. In these trials, short-term (3 week) anti-manic efficacy was demonstrated in a flexible dosage range of 1 mg to 6 mg per day [see Clinical Studies ( 14.2 , 14.3 )]. Risperidone doses higher than 6 mg per day were not studied. Pediatrics The initial dose is 0.5 mg once daily, administered as a single-daily dose in the morning or evening. The dose may be adjusted at intervals of 24 hours or greater, in increments of 0.5 mg or 1 mg per day, as tolerated, to the recommended target dose of 1 mg to 2.5 mg per day. Although efficacy has been demonstrated in studies of pediatric patients with bipolar mania at doses between 0.5 mg and 6 mg per day, no additional benefit was observed above 2.5 mg per day, and higher doses were associated with more adverse events. Doses higher than 6 mg per day have not been studied. Patients experiencing persistent somnolence may benefit from administering half the daily dose twice daily. Maintenance Therapy There is no body of evidence available from controlled trials to guide a clinician in the longer-term management of a patient who improves during treatment of an acute manic episode with risperidone. While it is generally agreed that pharmacological treatment beyond an acute response in mania is desirable, both for maintenance of the initial response and for prevention of new manic episodes, there are no systematically obtained data to support the use of risperidone in such longer-term treatment (i.e., beyond 3 weeks). The physician who elects to use risperidone for extended periods should periodically re-evaluate the long-term risks and benefits of the drug for the individual patient. 2.3 Irritability Associated with Autistic Disorder – Pediatrics (Children and Adolescents) The dosage of risperidone should be individualized according to the response and tolerability of the patient. The total daily dose of risperidone can be administered once daily, or half the total daily dose can be administered twice daily. For patients with body weight less than 20 kg, initiate dosing at 0.25 mg per day. For patients with body weight greater than or equal to 20 kg, initiate dosing at 0.5 mg per day. After a minimum of four days, the dose may be increased to the recommended dose of 0.5 mg per day for patients less than 20 kg and 1.0 mg per day for patients greater than or equal to 20 kg. Maintain this dose for a minimum of 14 days. In patients not achieving sufficient clinical response, the dose may be increased at intervals of 2 weeks or greater, in increments of 0.25 mg per day for patients less than 20 kg, or increments of 0.5 mg per day for patients greater than or equal to 20 kg. The effective dose range is 0.5 mg to 3 mg per day. No dosing data are available for children who weigh less than 15 kg. Once sufficient clinical response has been achieved and maintained, consider gradually lowering the dose to achieve the optimal balance of efficacy and safety. The physician who elects to use risperidone for extended periods should periodically re-evaluate the long-term risks and benefits of the drug for the individual patient. Patients experiencing persistent somnolence may benefit from a once-daily dose administered at bedtime or administering half the daily dose twice daily, or a reduction of the dose. 2.4 Dosing in Patients with Severe Renal or Hepatic Impairment For patients with severe renal impairment (Clcr< 30 mL/min) or hepatic impairment (10-15 points on Child Pugh System), the initial starting dose is 0.5 mg twice daily. The dose may be increased in increments of 0.5 mg or less, administered twice daily. For doses above 1.5 mg twice daily, increase in intervals of one week or greater [see Use in Specific Populations ( 8.6 and 8.7 )] . 2.5 Dose Adjustments for Specific Drug Interactions When risperidone is co-administered with enzyme inducers (e.g., carbamazepine), the dose of risperidone should be increased up to double the patient’s usual dose. It may be necessary to decrease the risperidone dose when enzyme inducers such as carbamazepine are discontinued [see Drug Interactions ( 7.1 )] . Similar effect may be expected with co-administration of risperidone with other enzyme inducers (e.g., phenytoin, rifampin, and phenobarbital). When fluoxetine or paroxetine is co-administered with risperidone, the dose of risperidone should be reduced. The risperidone dose should not exceed 8 mg per day in adults when co-administered with these drugs. When initiating therapy, risperidone should be titrated slowly. It may be necessary to increase the risperidone dose when enzyme inhibitors such as fluoxetine or paroxetine are discontinued [see Drug Interactions ( 7.1 )] .