Is it safe to take Nuplazid (Pimavanserin) with Seroquel (Quetiapine)?

From the Guidelines

Taking Nuplazid (pimavanserin) with Seroquel (quetiapine) requires cautious medical supervision due to the potential risk of QT interval prolongation, as both medications can affect heart rhythm, with quetiapine causing a mean QT prolongation of 6 ms 1. When considering the combination of these two medications, it's crucial to weigh the benefits against the potential risks, especially the risk of QT interval prolongation, which can lead to serious heart rhythm abnormalities.

• The decision to prescribe this combination should be based on a thorough assessment of the patient's medical history, current health status, and the potential benefits of the treatment.
• Patients on this combination should be closely monitored for signs of QT interval prolongation, such as irregular heartbeat, and other potential side effects like sedation, dizziness, and orthostatic hypotension.
• Regular ECG monitoring may be necessary to assess the heart's rhythm and detect any potential abnormalities early.
• It's essential for patients to report any unusual symptoms promptly to their healthcare provider, as these could indicate a serious interaction between the medications.
• Adjusting the dosage or stopping either medication should only be done under the guidance of a healthcare provider to avoid withdrawal symptoms or worsening of the underlying condition.

From the FDA Drug Label

7 DRUG INTERACTIONS 7. 1 Drugs Having Clinically Important Interactions with NUPLAZID

Table 2 Clinically Important Drug Interactions with NUPLAZID QT Interval Prolongation Clinical Impact:Concomitant use of drugs that prolong the QT interval may add to the QT effects of NUPLAZID and increase the risk of cardiac arrhythmia Intervention:Avoid the use of NUPLAZID in combination with other drugs known to prolong QT interval (e.g., Class 1A antiarrythmics, Class 3 antiarrythmics, certain antipsychotics or antibiotics) [see Warnings and Precautions (5.2)].

The FDA drug label does not explicitly mention Seroquel (Quetiapine) as a contraindication or interaction with Nuplazid (Pimavanserin). However, Seroquel is known to prolong the QT interval.

• To avoid potential cardiac arrhythmia, it is recommended to exercise caution when taking Nuplazid with Seroquel.
• The label advises to avoid concomitant use of NUPLAZID with drugs that prolong the QT interval.
• Since Seroquel can prolong the QT interval, it is recommended to avoid concomitant use of Nuplazid with Seroquel 2.

From the Research

Safety of Combining Nuplazid and Seroquel

• There is limited direct evidence on the safety of taking Nuplazid (Pimavanserin) with Seroquel (Quetiapine) 3, 4, 5, 6, 7.
• Studies suggest that Pimavanserin is the first-line treatment for mild psychotic symptoms in Parkinson's disease, while Quetiapine is often used off-label due to its relatively low risk of worsening motor function 3, 4, 5.
• However, Quetiapine has been associated with a significant decline in cognition, particularly in patients with reduced cognitive abilities 4.
• A comparative study of Pimavanserin and Quetiapine found that Pimavanserin resulted in lower rates of all-cause and psychiatric-related inpatient hospitalizations, as well as emergency room visits, compared to Quetiapine 6.
• There is no direct evidence on the safety of combining Nuplazid and Seroquel, but the available data suggest that Pimavanserin may be a safer option for patients with Parkinson's disease psychosis due to its lower risk of cognitive decline and motor worsening 4, 5, 6.

Efficacy of Pimavanserin and Quetiapine

• Pimavanserin has been shown to be effective in improving psychotic symptoms in patients with Parkinson's disease, without worsening motor function 3, 4, 5.
• Quetiapine has also been used to treat Parkinson's disease psychosis, but its efficacy is less well-established, and it may be associated with a higher risk of cognitive decline 4, 7.
• A systematic review of Quetiapine, Clozapine, and Pimavanserin treatment response in monogenic Parkinson's disease psychosis found that Quetiapine and Clozapine may be effective in some cases, but the evidence is limited, and Pimavanserin was not studied in this context 7.

Considerations for Combination Therapy

• The decision to combine Nuplazid and Seroquel should be made on a case-by-case basis, taking into account the individual patient's symptoms, medical history, and response to treatment 5.
• Patients with reduced cognitive abilities may be at higher risk of adverse effects from Quetiapine, and alternative treatments, such as Pimavanserin, may be preferred 4, 5.
• Further studies are needed to fully understand the safety and efficacy of combining Nuplazid and Seroquel, as well as the optimal treatment strategies for patients with Parkinson's disease psychosis 3, 4, 5, 6, 7.