Dosing Considerations: Refer to Special Populations as follows for dosing recommendations in the following patients: Geriatrics; Patients prone to hypotension; Patients with impaired liver function; Patients with impaired kidney function.
Recommended Dose and Dosage Adjustment: Adults: Schizophrenia and Related Psychotic Disorders: pms-RISPERIDONE can be administered on either a o.d. or b.i.d. schedule, generally beginning with 1 to 2 mg per day. The dose should be adjusted gradually over several days based on clinical response to a target dose of 4 to 6 mg per day. Some patients may benefit from lower initial doses and/or a slower adjustment schedule.
Further dosage adjustments, if indicated, should generally occur at intervals of not less than one week since steady state for the active metabolite would not be achieved for approximately one week in the typical patient. When dosage adjustments are necessary, small increments/decrements of 1 mg are recommended.
In controlled clinical trials, optimal therapeutic effects were seen in the 4 to 8 mg per day dose range. However, clinical experience indicates that in the majority of patients adequate therapeutic effect is achieved at the 6 mg per day dose. Doses above 10 mg per day have not been shown to be more efficacious than lower doses and were associated with more extrapyramidal symptoms and other adverse events.
The safety of risperidone has not been established above 16 mg total daily dose, administered twice daily. If administered once daily, safety has not been established beyond a single dose of 8 mg.
Switching from Other Antipsychotics: When medically appropriate, gradual discontinuation of the previous treatment, while pms-RISPERIDONE therapy is initiated, is recommended. In all cases, the period of overlapping antipsychotic administration should be minimized. When switching patients from depot antipsychotics, initiate pms-RISPERIDONE therapy in place of the next scheduled injection. The need for continuing existing antiparkinsonian medications should be re-evaluated periodically.
Maintenance Therapy: It is recommended that responding patients be continued on pms-RISPERIDONE at the lowest dose needed to maintain remission. Patients should be reassessed periodically to determine the need for maintenance treatment. While there is no body of evidence available to answer the question of how long the patient should be treated with pms-RISPERIDONE, the effectiveness of maintenance treatment is well established for many other antipsychotic drugs.
Severe Dementia of the Alzheimer Type: Physicians are advised to assess the risks and benefits of the use of pms-RISPERIDONE in elderly patients with dementia of the Alzheimer type, taking into account risk predictors for stroke or existing cardiovascular comorbidities in the individual patient (see Adults: Severe Dementia of the Alzheimer type - Symptomatic management of aggression and psychotic symptoms under Indications/Uses; Use in Elderly: Use in Geriatric Patients with Dementia under Precautions; Clinical Trial Adverse Drug Reactions: Elderly Patients with Severe Dementia and Cerebrovascular Adverse Events (CVAEs) in Elderly Patients with Dementia under Adverse Reactions).
Discontinuation should be considered if signs and symptoms of cerebrovascular adverse events occur.
A starting dose of pms-RISPERIDONE 0.25 mg b.i.d. is recommended. This dosage should be adjusted by increments of 0.25 mg per day approximately every 2 to 4 days. The optimal dose is 0.5 mg b.i.d. (1.0 mg per day) for most patients. Some patients, however, may benefit from higher doses up to a maximum of 1.0 mg b.i.d. (2.0 mg per day).
Periodic dosage adjustments (increase or decrease) or discontinuation of treatment should be considered because of the instability of the symptoms treated.
Since there is no experience in younger patients, dosage recommendations cannot be made.
Bipolar Mania: pms-RISPERIDONE should be administered on a once-daily schedule, starting with 2 mg to 3 mg per day. Dosage adjustments, based on clinical response and tolerability, should occur at intervals of not less than 24 hours and in dosage increments or decrements of 1 mg per day. Risperidone doses higher than 6 mg per day were not studied in patients with bipolar disorder. In two controlled trials, the most common daily dose was 1 - 4 mg/day. In each of the three controlled trials, risperidone was effective across the dose range used, although the effect size in the 3 - 4 mg/day mean modal dose group was larger than in the 5 - 6 mg/day mean modal dose group (mean modal dose is the average of the most frequent daily dose across the three trials).
The safety and effectiveness of risperidone for long-term use and for prophylactic use in bipolar disorder have not been evaluated. Physicians who elect to use pms-RISPERIDONE for extended periods should periodically re-evaluate the long-term risks and benefits of the drug for the individual patient.
Special Populations: Geriatrics: Risperidone is substantially excreted by the kidneys. Thus, the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, caution should be taken in dose selection and titration. It may also be useful to monitor renal function in these patients (see Pharmacology: Pharmacokinetics: Special Populations and Conditions - Table 3 under Actions; Use in Elderly under Precautions).
In elderly schizophrenic patients, the doses of pms-RISPERIDONE should be adjusted slowly from a 0.25 mg b.i.d. starting dose to a maximum daily dose of 3 mg. Since the elimination of risperidone is somewhat slower in these patients, the potential for accumulation should be considered (see Pharmacology: Pharmacokinetics: Special Populations and Conditions - Table 3 under Actions).
Patients Prone to Hypotension: Caution should be exercised in patients prone to hypotension and the use of lower starting doses of 0.25 to 0.5 mg b.i.d. should be considered.
Patients with Impaired Liver Function: pms-RISPERIDONE should be used with caution in patients with hepatic impairment.
Patients with impaired hepatic function have increases in plasma concentration of the free fraction of risperidone and this may result in an enhanced effect. In general, starting and consecutive dosing should be halved, and dose titration should be slower for patients with hepatic impairment, administered on a b.i.d. schedule.
In patients with schizophrenia and related psychotic disorders with impaired liver function, the starting dose should be 0.25 to 0.5 mg b.i.d. This dosage can be individually adjusted in 0.5 mg b.i.d. increments to 1 to 2 mg b.i.d. Increases to dosages above 1.5 mg b.i.d. should generally occur at intervals of at least 1 week (see Pharmacology: Pharmacokinetics: Special Populations and Conditions - Table 3 under Actions; Hepatic/Biliary/Pancreatic under Precautions).
Patients with Impaired Kidney Function: pms-RISPERIDONE should be used with caution in patients with renal impairment.
Patients with renal impairment have less ability to eliminate the active antipsychotic fraction than normal adults. In general, starting and consecutive dosing should be halved, and dose titration should be slower for patients with renal impairment, administered on a b.i.d. schedule. The recommended initial dose is 0.5 mg b.i.d. and dosage increases should be in increments of no more than 0.5 mg b.i.d. Increases to dosages above 1.5 mg b.i.d. should generally occur at intervals of at least 1 week. In some patients, slower titration may be medically appropriate (see Pharmacology: Pharmacokinetics: Special Populations and Conditions - Table 3 under Actions; Renal under Precautions).
Missed Dose: The missed dose should be taken at the next scheduled dose. Doses should not be doubled.
Administration: pms-RISPERIDONE may be given as tablets or oral solution. All may be taken with or without meals. In order to avoid orthostatic hypotension, the dose of pms-RISPERIDONE should be adjusted gradually.