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Verapamil + paroxetine

University of California, Irvine · FDA-approved active Small molecule

This combination uses verapamil (a calcium channel blocker) to inhibit drug efflux transporters, thereby increasing paroxetine (an SSRI) bioavailability and CNS penetration.

This combination uses verapamil (a calcium channel blocker) to inhibit drug efflux transporters, thereby increasing paroxetine (an SSRI) bioavailability and CNS penetration. Used for Depression (investigational combination to enhance SSRI efficacy).

At a glance

Generic nameVerapamil + paroxetine
SponsorUniversity of California, Irvine
Drug classSSRI + calcium channel blocker combination
TargetP-glycoprotein (MDR1/ABCB1), L-type calcium channels
ModalitySmall molecule
Therapeutic areaPsychiatry / Neurology
PhaseFDA-approved

Mechanism of action

Verapamil blocks P-glycoprotein and other efflux transporters that normally pump paroxetine out of cells and across the blood-brain barrier. By inhibiting these transporters, verapamil increases paroxetine concentrations in the brain and systemic circulation, potentially enhancing antidepressant efficacy at lower doses. This is a pharmacokinetic interaction strategy rather than a direct therapeutic mechanism.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results