Modafinil taken by students as a “smart drug” could reduce effectiveness of hormonal contraception: CEU Clinical Update

This CEU Clinical Update highlights growing concerns about the off-licence use of modafinil as a “smart drug” by university students and the potential impact it may have on risk of unintended pregnancy in women using hormonal contraception.

It has been reported that as many as one in five UK university students could be using modafinil (or similar drug) as a ‘smart drug’ to enhance cognitive function during exam periods. Although it is a prescription-only medication, modafinil can be easily purchased over the internet. Some universities view unauthorised use of a medicine like this as cheating. Student media often report the potential benefits of using modafinil without cautioning about side-effects and the potential drug interactions with other concomitant medications. Women may be putting themselves at risk of an unintended pregnancy as there is a possible interaction between modafinil and hormonal contraception.

Drug interactions between ethinylestradiol and modafinil have been reported, most likely through the CYP3A4 enzyme pathway. It is possible that this interaction could also affect progestogens. Modafinil could therefore reduce the contraceptive effectiveness of combined hormonal contraceptives (including the combined pill, patch and vaginal ring), the progestogen-only pill and the subdermal implant. Women taking modafinil should be advised to use contraceptive methods not affected by enzyme-inducing drugs, such as a copper intrauterine devices (Cu-IUD), levonorgestrel releasing intrauterine system (LNG-IUS) or depot medroxyprogesterone acetate (DMPA) to ensure contraceptive efficacy.

The CEU advises that healthcare professionals must warn women using hormonal contraception and taking modafinil off-licence of the potential impact on contraceptive efficacy and counsel them regarding appropriate methods of contraception to use.