Can I take St John's wort and Contraceptive pill together?
Drug interaction guide
Originally published 25 Jan 2026
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
- Language
- Discussion
- Audio Version
- Add to preferred sources on Google
Taking St John's Wort can make your contraceptive pill much less effective. This significantly increases the risk of an unplanned pregnancy. You may also experience 'breakthrough bleeding' or spotting between periods.
Why this happens
St John's Wort is a 'liver enzyme inducer'. This means it speeds up the process by which your liver breaks down the hormones (oestrogen and progestogen) found in the contraceptive pill. Because the hormones are cleared from your body much faster than normal, their levels drop too low to reliably prevent pregnancy.
What you should do
You should not take St John's Wort if you are using any form of hormonal contraception (including the combined pill, the mini-pill, implants, or patches). If you have already started taking it, continue using your pill but use an extra barrier method of contraception (like condoms) immediately. Speak to your GP or pharmacist about alternative treatments for your mood that do not interfere with your birth control.
Important precautions
Contraceptive failure
St John's wort significantly reduces the effectiveness of the contraceptive pill. This can lead to unplanned pregnancy. You must use an additional barrier method of contraception (such as condoms) or switch to a non-hormonal contraceptive method while taking St John's wort and for four weeks after stopping it.
Depression and Mental Health
Like other antidepressants, St John's wort may increase the risk of suicidal thoughts or self-harm, particularly when first starting treatment. Seek immediate medical help if your mood worsens.
Drug Interactions
St John's wort significantly reduces the effectiveness of many essential medicines, including the contraceptive pill, blood thinners (warfarin), epilepsy medications, and organ transplant drugs. Do not start it without a pharmacist checking your current medications.
Serotonin Syndrome
Taking St John's wort with other antidepressants or triptans (for migraine) can cause serotonin syndrome, a potentially life-threatening condition involving high fever, agitation, and muscle rigidity.
Photosensitivity
St John's wort can make your skin significantly more sensitive to sunlight, leading to severe sunburn or skin reactions even with limited exposure.
Food and drink warnings
Alcohol
It is best to avoid or strictly limit alcohol while taking St John's Wort. Combining the two can increase drowsiness and dizziness, and may worsen the side effects of the herbal remedy.
It is best to avoid or strictly limit alcohol while taking the pill. While alcohol does not directly stop the pill from working, being intoxicated increases the risk of forgetting to take your pill or vomiting shortly after taking it, which renders the contraception ineffective.
Foods high in Tyramine (e.g., aged cheeses, cured meats, soy sauce, marmite, overripe fruit)
While less common than with older prescription antidepressants, St John's Wort can potentially interact with tyramine-rich foods, leading to a sudden, dangerous increase in blood pressure (hypertensive crisis). You should consume these foods in moderation.
Using other medicines
Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
Patient picks for Drug interactions

Drug interactions checker
Can I take Allopurinol and Nortriptyline together?
There is no known direct interaction between allopurinol and nortriptyline. However, both medications can occasionally cause side effects that affect the liver or blood counts. Taking them together does not typically increase these risks, but it is important to be aware of how you feel.

Drug interactions checker
Can I take Flecainide and Wegovy together?
Wegovy (semaglutide) can slow down how quickly your stomach empties. This might change how your body absorbs flecainide, which is a medicine that needs to be kept at very specific levels in your blood to work safely and effectively. Additionally, both medications can occasionally affect your heart rhythm or heart rate.
Article history
The information on this page is written and peer reviewed by qualified clinicians.
Article also available in English, German, Spanish, French, Italian, Portuguese, Hindi, Hebrew, Arabic, and Swedish.
25 Jan 2026 | Originally published
Join the conversation
Share your thoughts or experiences with others in our patient communities.

Ask, share, connect.
Browse discussions, ask questions, and share experiences across hundreds of health topics.

Feeling unwell?
Assess your symptoms online for free
Sign up to the Patient newsletter
Your weekly dose of clear, trustworthy health advice - written to help you feel informed, confident and in control.
By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.
More in drug interactions checker
- Can I take Alcohol and Atorvastatin together?
- Can I take Amitriptyline and Oxycodone together?
- Can I take Bactrim and Venlafaxine together?
- Can I take Black cohosh and Vitamin D together?
- Can I take Chaga and Shiitake together?
- Can I take Cod liver oil and Paracetamol together?
- Can I take Colecalciferol and Trazodone together?
- Can I take Fluanxol and Prozac together?
- Can I take Guanfacine and Tizanidine together?
- Can I take Ibuprofen and Diclofenac together?
- Can I take Iron supplements and Sedoxil together?
- Can I take Lion's mane and Turkey tail together?
- Can I take Losartan and Metformin together?
- Can I take Magnesium and Simvastatin together?
- Can I take Mirtazapine and Clopidogrel together?
- Can I take Mounjaro and Paracetamol together?
- Can I take Reishi and Shiitake together?
- Can I take Sertraline and Tramadol together?
- Can I take Warfarin and Ibuprofen together?