Risperidone depot microspheres release is characterized by which release profile?

Risperidone depot microspheres release is characterized by which release profile?

• A. Rapid release with therapeutic levels in 24 hours
• B. Gradually hydrolyzed and released, reaching therapeutic levels in 3-4 weeks
• C. Immediate peak after administration followed by a rapid decline
• D. Release that varies unpredictably between patients

Answer: (B)

Depot microsphere formulations release drug through slow degradation of the polymer around the drug, yielding a steady, long-acting release. For risperidone in this depot form, water slowly penetrates the microspheres and the polymer hydrolyzes over time, so the medication is released gradually rather than all at once. Because of this mechanism, therapeutic plasma levels take several weeks to establish—typically about three to four weeks—and then remain sustained with continued release. This aligns with a gradual, hydrolysis-driven release profile rather than a rapid burst or immediate peak, and it tends to be more predictable than an uncontrolled, variable release. So the description that fits best is gradual hydrolysis and release, reaching therapeutic levels in 3-4 weeks.

Depot microsphere formulations release drug through slow degradation of the polymer around the drug, yielding a steady, long-acting release. For risperidone in this depot form, water slowly penetrates the microspheres and the polymer hydrolyzes over time, so the medication is released gradually rather than all at once. Because of this mechanism, therapeutic plasma levels take several weeks to establish—typically about three to four weeks—and then remain sustained with continued release. This aligns with a gradual, hydrolysis-driven release profile rather than a rapid burst or immediate peak, and it tends to be more predictable than an uncontrolled, variable release. So the description that fits best is gradual hydrolysis and release, reaching therapeutic levels in 3-4 weeks.