Serotonin-norepinephrine reuptake inhibitor (SNRI)
Venlafaxine with the birth control pill
Many women of reproductive age take a combined or progestogen-only oral contraceptive while also using a chronic medication such as Venlafaxine (Venlafaxine). The combination is generally fine at 37.5mg, 75mg, 150mg, but a small number of medications can reduce contraceptive efficacy meaningfully and need either a backup method or a switch.
How Venlafaxine can affect contraceptive efficacy
Combined and progestogen-only contraceptives are metabolised through CYP3A4. Strong CYP3A4 inducers (some antiepileptics, rifampicin, St John's Wort) lower contraceptive plasma levels and reduce efficacy. Whether Venlafaxine acts on CYP3A4 determines whether Venlafaxine affects contraception. Most agents in Serotonin-norepinephrine reuptake inhibitor (SNRI) have no clinically meaningful effect on the pill at 37.5mg, 75mg, 150mg.
Practical guidance
According to the prescribing information for Venlafaxine, women on hormonal contraception should review Venlafaxine with the prescribing pharmacist or doctor. Where an interaction is documented, additional barrier contraception or switching to a non-oral method (IUD, implant) for the duration of Venlafaxine therapy is the standard mitigation.
Frequently asked questions
Will Venlafaxine make my pill less effective? ▾
Most Serotonin-norepinephrine reuptake inhibitor (SNRI) medications at 37.5mg, 75mg, 150mg do not affect oral contraceptive efficacy. The exceptions are CYP3A4-inducing drugs and a small number of others. The prescribing information for Venlafaxine states whether the interaction is meaningful.
Do I need a backup contraceptive on Venlafaxine? ▾
Backup contraception is needed only when there is a documented interaction between Venlafaxine and the contraceptive method. For most users at 37.5mg, 75mg, 150mg, no backup is required. The pharmacist confirms whether Venlafaxine interacts with hormonal contraception.
Products containing Venlafaxine
More on Venlafaxine
- With alcoholVenlafaxine and alcohol — is it safe to drink?
- With foodShould Venlafaxine be taken with food?
- Side effectsVenlafaxine side effects: common, rare and warning signs
- Dosage guideVenlafaxine dosage guide: how much to take and when
- OnsetHow fast does Venlafaxine start working?
- DurationHow long does Venlafaxine last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.