From the Guidelines
The starting dose of Risperdal Consta (risperidone long-acting injection) is 25 mg administered intramuscularly every two weeks, given in conjunction with oral risperidone for the first 3 weeks. However, the provided evidence does not specifically mention the starting dose of Risperdal Consta. The evidence provided in 1 discusses the treatment of behavior and mood disorders in Alzheimer's disease, including the use of antipsychotic drugs, but it only mentions the initial dosage of oral Risperidone, which is 0.25 mg per day at bedtime. It is essential to note that Risperdal Consta is a long-acting injection, and its dosing regimen may differ from that of oral Risperidone. Given the lack of specific information on Risperdal Consta in the provided evidence, the recommended starting dose is based on general medical knowledge and guidelines for the use of long-acting antipsychotic injections. Some key points to consider when initiating Risperdal Consta include:
- Ensuring the patient tolerates oral Risperidone before starting the long-acting injection
- Administering the injection by a healthcare professional in the deltoid or gluteal muscle, alternating between sides for each dose
- Monitoring the patient closely for the first few months to assess response and side effects
- Making dose adjustments in 12.5 mg increments, not more frequently than every 4 weeks, up to a maximum of 50 mg every 2 weeks.
From the FDA Drug Label
A total of 501 patients were treated during a 26-week open-label period with Risperidone for Extended-Release Injectable Suspension (starting dose of 25 mg, and titrated, if deemed clinically desirable, to 37.5 mg or 50 mg; in patients not tolerating the 25 mg dose, the dose could be reduced to 12. 5 mg).
The starting dose of Risperdal (Risperidone) Consta is 25 mg.
- The dose can be titrated to 37.5 mg or 50 mg if deemed clinically desirable.
- In patients who do not tolerate the 25 mg dose, the dose can be reduced to 12.5 mg 2.
From the Research
Starting Dose of Risperdal (Risperidone) Consta
The starting dose of Risperdal (Risperidone) Consta can vary depending on the patient's previous oral risperidone dose.
- For patients who were previously on an oral risperidone dose of 3 mg/day or less, the recommended starting dose is 25 mg of Risperdal Consta every 2 weeks 3.
- For patients who were previously on an oral risperidone dose of more than 3 mg/day but of 5 mg/day or less, the recommended starting dose is 37.5 mg of Risperdal Consta every 2 weeks 3.
- For patients who were previously on an oral risperidone dose of more than 5 mg/day, the recommended starting dose is 50 mg of Risperdal Consta every 2 weeks 3.
Pharmacokinetics and Tolerability
The pharmacokinetics and tolerability of long-acting risperidone have been evaluated in several studies, which have shown that it is generally well tolerated with a low incidence of injection site pain and an otherwise similar profile of adverse effects to the oral formulation 4, 5.
- The study by 5 found that the 90% confidence intervals for the i.m./oral ratios of the mean steady-state plasma-AUC, corrected for dosing interval, and of the average plasma concentration of the active moiety were within the range of 80-125%, indicating bioequivalence of the i.m. and oral formulations.
- However, mean steady-state peak concentrations of the active moiety were 25-32% lower with i.m. than oral dosing, and fluctuations in plasma active-moiety levels were 32-42% lower with the i.m. than oral regimen 5.