How many days after the loading dose of Invega Sustenna (paliperidone) is the first maintenance dose administered?

Invega Sustenna: First Maintenance Dose Timing After Loading Dose

The first maintenance dose of Invega Sustenna (paliperidone palmitate) should be administered 1 week (7 days) after the initial loading dose.

Dosing Schedule for Invega Sustenna

Invega Sustenna follows a specific dosing schedule that consists of:

1. Initial Loading Dose:

   • Day 1: 234 mg injection (deltoid muscle)
   • Followed by second dose exactly 1 week later

2. Second Loading Dose:

   • Day 8 (7 days after initial dose): 156 mg injection (deltoid muscle)

3. First Maintenance Dose:

   • Day 36 (1 month/4 weeks after Day 8 dose): 117 mg (or prescribed maintenance dose)
   • Can be administered in either deltoid or gluteal muscle

Clinical Rationale for This Schedule

The 7-day interval between loading doses is critical because:

• It allows for rapid attainment of therapeutic concentrations without oral supplementation 1
• The biphasic pharmacokinetic profile of paliperidone palmitate requires proper timing to maintain consistent drug levels 1
• Deviating from this schedule could result in:
  • Transient excursions above therapeutic plasma concentrations (increasing risk of adverse effects)
  • Delay in attaining therapeutic plasma concentrations (increasing risk of relapse)

Important Considerations

• No Oral Supplementation Required: Unlike some other long-acting injectables, Invega Sustenna does not recommend bridging with oral antipsychotics 2

• Dose Adjustments: For patients previously on oral risperidone ≥4 mg/day, bridging with oral medication for ≥7 days after the first paliperidone injection may be beneficial in reducing hospitalization days 2

• Monitoring: Regular monitoring for adverse effects is essential, particularly during the initiation phase

• Common Side Effects: Watch for injection site reactions, extrapyramidal symptoms, tachycardia, hypotension, and QT prolongation 1

Long-term Maintenance

After the initial loading and first maintenance dose, subsequent maintenance doses are administered monthly (every 4 weeks). Consistent timing of injections is important to maintain therapeutic levels and prevent relapse.

For patients who demonstrate good response and stability on Invega Sustenna, longer-acting formulations such as Invega Trinza (administered every 3 months) or Invega Hafyera (administered every 6 months) may be considered after appropriate stabilization periods 3.

Conclusion

Adhering to the proper timing between loading doses and the first maintenance dose is crucial for achieving optimal clinical outcomes with Invega Sustenna. The first maintenance dose should be given exactly 1 month (4 weeks) after the second loading dose, which occurs 1 week after the initial loading dose.