From the FDA Drug Label
NUPLAZID can be taken with or without food [see Clinical Pharmacology (12.3)]. The recommended dose of NUPLAZID is 34 mg taken orally once daily, without titration. Coadministration with Strong CYP3A4 Inhibitors The recommended dose of NUPLAZID when coadministered with strong CYP3A4 inhibitors is 10 mg, taken orally as one tablet once daily [see Drug Interactions (7. 1)]. Coadministration with Strong or Moderate CYP3A4 Inducers Avoid concomitant use of strong or moderate CYP3A4 inducers with NUPLAZID [see Drug Interactions (7. 1)].
Key Considerations:
- Nuplazid (pimavanserin) can be taken with or without food.
- The recommended dose is 34 mg once daily.
- Seroquel (quetiapine) is a CYP3A4 substrate and inhibitor, but its effect on pimavanserin is not explicitly stated in the provided drug labels.
- However, CYP3A4 inhibitors require a dose reduction of Nuplazid to 10 mg once daily.
- It is not explicitly stated whether Seroquel can be taken concomitantly with Nuplazid at bedtime, but considering the potential interaction, caution is advised.
- Consultation with a healthcare professional is necessary to determine the safety and efficacy of concomitant use of Nuplazid and Seroquel at bedtime for Parkinson's disease psychosis 1 1.
From the Research
Initiating Nuplazid (pimavanserin) with Seroquel (quetiapine) at bedtime for Parkinson's disease psychosis is generally not recommended. These medications should not be used concurrently due to overlapping mechanisms and increased risk of adverse effects. Nuplazid is specifically FDA-approved for Parkinson's disease psychosis and works as a selective serotonin inverse agonist, primarily affecting 5-HT2A receptors without the dopamine-blocking effects that can worsen motor symptoms. Seroquel, an atypical antipsychotic, blocks both dopamine and serotonin receptors and may worsen Parkinson's motor symptoms.
Key Considerations
- According to a recent study 2, pimavanserin is recommended as a first-line antipsychotic therapy based on its established safety and efficacy.
- Another study 3 found that pimavanserin and clozapine demonstrated significant improvement in psychosis without affecting motor function, while quetiapine was associated with a significant decline in cognition.
- The combination of Nuplazid and Seroquel could potentially increase the risk of QT prolongation, sedation, confusion, and other adverse effects without providing additional therapeutic benefit.
Recommended Approach
If treatment is needed, Nuplazid (34 mg once daily) should be used alone as first-line therapy for Parkinson's disease psychosis. If a patient is currently taking Seroquel, a gradual cross-taper under medical supervision would be appropriate rather than adding Nuplazid to existing Seroquel therapy. Always consult with a neurologist or psychiatrist experienced in treating Parkinson's disease psychosis before making medication changes.