Major
Probable
Description
Diazepam and quetiapine together significantly increase CNS depression and carry risk of severe sedation and cardiorespiratory compromise.
Mécanisme
Additive CNS depression through complementary receptor mechanisms (GABA-A vs. H1/alpha-1/D2 blockade); quetiapine also prolongs QT, adding cardiac risk.
Signification clinique
Excess sedation and cardiovascular events are documented with the combination; particularly risky in elderly or medically ill patients.
Prise en charge
Use at minimum doses only when clearly indicated; monitor sedation level, ECG, and vital signs.