Coadministration has not been studied. Boosted darunavir is expected to increase quetiapine concentrations due to CYP3A inhibition. Concomitant administration of boosted darunavir and quetiapine is contraindicated as it may increase quetiapine-related toxicity. Increased concentrations of quetiapine may lead to coma.

Coadministration with darunavir/ritonavir may increase quetiapine concentrations. 
Initiation of darunavir with ritonavir in patients taking quetiapine: Consider alternative antiretroviral therapy to avoid increases in quetiapine exposures. If coadministration is necessary, reduce the quetiapine dose to 1/6 of the current dose and monitor for quetiapine-associated adverse reactions. Refer to the quetiapine prescribing information for recommendations on adverse reaction monitoring.
Initiation of quetiapine in patients taking darunavir with ritonavir: Refer to the quetiapine prescribing information for initial dosing and titration of quetiapine.