Modafinil/Armodafinil - Birth Control and Pregnancy
Updated: Sep 20
Updated September 2026
Did you know that modafinil and armodafinil can reduce the effectiveness of hormonal contraceptives?
Modafinil (Modavigil) and armodafinil (Nuvigil) are wake-promoting medications used to treat excessive daytime sleepiness associated with narcolepsy and some other sleep disorders. They are also prescribed off-label for some people with Idiopathic Hypersomnia.
There are two particularly important things people who could become pregnant need to know about these medications:
1. Modafinil and armodafinil can make hormonal contraception less effective.
2. Modafinil and armodafinil should not be used during pregnancy.
Contraception
Modafinil and armodafinil can increase the activity of enzymes involved in breaking down some hormonal contraceptives. This can reduce the amount of contraceptive hormone in the body and potentially reduce its effectiveness.
This interaction can affect steroidal/hormonal contraceptives including:
contraceptive pills
contraceptive implants
contraceptive injections
hormone-releasing intrauterine devices (IUDs)
Current Australian Consumer Medicine Information advises people using hormonal contraception to use an alternative non-hormonal method of contraception together with their current contraceptive while taking modafinil or armodafinil and for two months after stopping treatment.
This is important because the effect on hormonal contraception does not necessarily disappear as soon as the medication is stopped.
If you take modafinil or armodafinil and use hormonal contraception, speak to your doctor or pharmacist about contraception that is appropriate for you.
Why was the advice changed from one month to two months?
Older information, including the original version of this article and our previous factsheet, advised using additional contraception for one month after stopping modafinil or armodafinil.
Current Australian Product Information now specifies two months.
Australian Modavigil information: https://www.safetyandquality.gov.au/medicine-finder/modavigil
Australian Nuvigil information: https://www.safetyandquality.gov.au/medicine-finder/nuvigil
What does the research tell us about the contraceptive interaction?
A clinical study examined the effect of modafinil on ethinyl estradiol, a hormone used in combined oral contraceptives. Modafinil altered ethinyl estradiol exposure and demonstrated its ability to induce CYP3A4/5, an enzyme system involved in the metabolism of many medicines.
It is important not to interpret this study as showing that all contraceptives become a particular percentage less effective. The study measured changes in the blood concentration and exposure of ethinyl estradiol. It did not measure pregnancy rates or establish a percentage risk of contraceptive failure.
Robertson P Jr, Hellriegel ET, Arora S, Nelson M. Effect of modafinil on the pharmacokinetics of ethinyl estradiol and triazolam in healthy volunteers. Clinical Pharmacology & Therapeutics. 2002;71(1):46-56. https://pubmed.ncbi.nlm.nih.gov/11823757/
Pregnancy
In Australia, modafinil and armodafinil are Pregnancy Category D and are contraindicated during pregnancy.
Current Australian Product Information states that, based on human experience, modafinil and armodafinil are suspected to cause congenital malformations and spontaneous abortion when taken during pregnancy.
If you could become pregnant, the current Australian Consumer Medicine Information also advises having a pregnancy test to confirm that you are not pregnant within one week before starting treatment.
If you become pregnant while taking modafinil or armodafinil, contact your doctor immediately. The current Australian Consumer Medicine Information instructs patients who become pregnant while taking either medication to stop taking it and tell their doctor immediately.
What does the pregnancy research show?
Our understanding of the pregnancy risk has changed considerably since this article was first published in 2018.
Early concern came from the US Provigil/Nuvigil Pregnancy Registry and other post-marketing data, which reported a higher than expected number of major congenital malformations following exposure to modafinil or armodafinil during pregnancy.
The final results of the 14-year Provigil/Nuvigil Pregnancy Exposure Registry were published in 2025. Among 137 prospective live births, major congenital malformations were reported in 13.1%, and in 13.7% following first-trimester exposure, compared with a population-based rate of approximately 3%.
The researchers noted important limitations and conflicting findings in the wider literature, so these figures should not be interpreted as establishing the precise level of risk for an individual pregnancy.
Kaplan S, Carneal-Frazer N, Braverman DL, et al. Pregnancy and Fetal Outcomes Following Prenatal Exposure to Modafinil and/or Armodafinil: A 14-Year Registry Study. Neurology Clinical Practice. 2025;15(6):e200551. https://www.neurology.org/doi/10.1212/CPJ.0000000000200551
A large French study published in 2026 added further information. It included 865 children prenatally exposed to modafinil. The researchers found an increased risk of major congenital anomalies when modafinil exposure was compared with methylphenidate exposure, but no clear increase when compared with a matched unexposed population. They concluded that a large increase in risk appears unlikely, but a moderate increase in the risk of birth defects cannot be excluded.
Kanoun S, et al. Prenatal Exposure to Modafinil and the Risk of Major Congenital Anomalies and Other Adverse Neonatal and Pediatric Outcomes. Pharmacoepidemiology and Drug Safety. 2026. https://doi.org/10.1002/pds.70448
Despite some differences between studies, the current Australian regulatory advice has not changed: modafinil and armodafinil are contraindicated during pregnancy.
Breastfeeding
The original version of this article included a 2018 case report that measured the transfer of modafinil into breast milk. Since then, Australian prescribing information has been updated.
Current Australian Product Information does not recommend breastfeeding while taking modafinil or armodafinil.
There is still limited information about exposure through human breast milk. If you are breastfeeding or planning to breastfeed, discuss your medication with your doctor.
The original breast milk case report can be read here:
Aurora RN, Bista SR, Casey KR, et al. Evaluating Transfer of Modafinil Into Human Milk During Lactation: A Case Report. Journal of Clinical Sleep Medicine. 2018. https://pubmed.ncbi.nlm.nih.gov/30518447/
Where can I find the current Australian medicine information?
Modavigil (modafinil)Australian Consumer Medicine Information and Product Information: https://www.safetyandquality.gov.au/medicine-finder/modavigil
Nuvigil (armodafinil)Australian Consumer Medicine Information and Product Information: https://www.safetyandquality.gov.au/medicine-finder/nuvigil
The TGA updated the pregnancy safety information for armodafinil in June 2025 and modafinil in July 2025, including information about congenital malformations and spontaneous abortion:
Always read the Consumer Medicine Information supplied with your medication and speak to your doctor or pharmacist if you have questions about contraception, pregnancy, breastfeeding or your medication.
