Thioridazine levels are expected to be increased by fluoxetine,
fluvoxamine (225% rise seen),
paroxetine, and possibly escitalopram.
The US manufacturers of fluoxetine,
fluvoxamine, and
paroxetine, contraindicate the concurrent use of as raised levels increase the risk of QT prolongation, see drugs that prolong the QT interval. The use of
thioridazine is also contraindicated for 5 weeks after fluoxetine has been stopped. It has been suggested that the dose of
thioridazine may need to be reduced when it is given with escitalopram.