What dose of Uzedy (long-acting antipsychotic) is equivalent to 2mg of risperidone (Risperdal) twice daily for a 30-day injection?

Uzedy Dosing Equivalent to Risperidone 2mg Twice Daily

For a patient currently taking risperidone 2mg twice daily (4mg/day total), the equivalent Uzedy dose for a 30-day injection would be 25mg every 2 weeks (biweekly), not monthly. However, I must clarify that Uzedy is administered every 2 weeks or monthly depending on the formulation, not as a "30-day injection" per se.

Critical Clarification on Uzedy Dosing Schedule

• Uzedy is not administered as a true "30-day" injection - it is given either every 2 weeks (biweekly) or every 4 weeks (monthly) depending on the specific product formulation
• The question appears to conflate risperidone long-acting injection (Risperdal Consta, given every 2 weeks) with other monthly formulations

Dose Conversion from Oral Risperidone to Long-Acting Injectable

Based on the most rigorous pharmacokinetic study available, for oral risperidone 4mg/day, the equivalent long-acting risperidone dose is 37.5mg every 2 weeks 1.

Evidence-Based Conversion Algorithm:

• Oral risperidone ≤3mg/day → 25mg LAI every 2 weeks 1
• Oral risperidone >3mg to ≤5mg/day → 37.5mg LAI every 2 weeks 1
• Oral risperidone >5mg/day → 50mg LAI every 2 weeks 1

Since your patient is on 4mg/day oral risperidone, the appropriate dose is 37.5mg every 2 weeks 1.

Important Implementation Considerations

Oral Supplementation Period

• Continue oral risperidone for the first 3 weeks after the initial LAI injection, as significant drug release from microspheres does not begin until week 3 2
• Steady-state plasma concentrations are not reached until after the fourth injection 2

Dosing Optimization Context

• The optimal target dose for most patients with oral risperidone is 4mg/day, which achieves ideal D2 receptor occupancy of 70-80% with minimal extrapyramidal symptom (EPS) risk 3, 4
• Doses above 6mg/day do not demonstrate greater efficacy and are associated with significantly more EPS 5, 4

Common Pitfalls to Avoid

• Do not use the older conversion guidelines that suggested 25mg LAI for oral doses ≤4mg/day - the 48-week pharmacokinetic study showed this led to increased relapse tendency and decreased serum metabolite concentrations 1
• Do not skip the oral supplementation period during the first 3 weeks, as this will result in subtherapeutic drug levels 2
• Monitor for lower EPS with LAI formulation - the long-acting injection showed reduced extrapyramidal symptoms compared to equivalent oral doses in controlled studies 1