Low-Ogestrel Drug Interactions: What to Avoid and What to Tell Your Doctor

If you take any other medications — prescription, over-the-counter, or herbal — it's important to know whether they interact with Low-Ogestrel. Some drugs can reduce Low-Ogestrel's effectiveness and increase your risk of unintended pregnancy. Others can change how your body processes different medications when combined with Low-Ogestrel.

This guide covers the most clinically important drug interactions for Low-Ogestrel, organized by severity.

Drugs That Are Contraindicated With Low-Ogestrel

These combinations should be avoided entirely:

Ombitasvir/paritaprevir/ritonavir ± dasabuvir (Viekira Pak, Technivie) — Hepatitis C combination medications. Co-administration with ethinyl estradiol-containing pills causes significant ALT (liver enzyme) elevations. Low-Ogestrel must be stopped and a non-estrogen method used during and after treatment.

Fezolinetant (Veozah) — Used for menopausal hot flashes. Ethinyl estradiol inhibits CYP1A2, which dramatically increases fezolinetant levels. Co-administration is contraindicated.

Drugs That Reduce Low-Ogestrel's Effectiveness (Major Risk of Contraceptive Failure)

These medications work by inducing liver enzymes (particularly CYP3A4), which speed up the breakdown of the hormones in Low-Ogestrel, lowering their levels in your blood and potentially allowing ovulation to occur:

Rifampin (Rifadin), Rifabutin (Mycobutin), Rifapentine — Antibiotics/antibiologics used for tuberculosis. Rifampin is one of the strongest enzyme inducers known and dramatically reduces hormone levels. Use an additional non-hormonal contraceptive method during rifampin treatment and for at least 28 days after stopping.

Carbamazepine (Tegretol), Phenytoin (Dilantin), Phenobarbital, Oxcarbazepine — Anti-seizure medications. These enzyme inducers decrease contraceptive hormone levels. Use additional backup contraception and for at least 28 days after stopping.

St. John's Wort (Hypericum perforatum) — Herbal supplement commonly used for mild depression. St. John's Wort is a CYP3A4 inducer that can reduce hormone levels and increase breakthrough bleeding. It is considered a major interaction — avoid taking Low-Ogestrel with St. John's Wort.

Modafinil (Provigil) — Used for narcolepsy/shift-work sleep disorder. Moderate CYP3A4 inducer; may reduce Low-Ogestrel's effectiveness. Use backup contraception.

HIV antiretroviral medications (ritonavir, lopinavir, efavirenz, nevirapine) — Many antiretrovirals either induce or inhibit CYP3A4. Some reduce hormone levels; others increase them. Ask your HIV specialist and gynecology provider to review this interaction based on your specific regimen.

What About Regular Antibiotics?

This is a common concern. Current evidence and FDA guidance no longer suggests that most common antibiotics (like amoxicillin, doxycycline, or azithromycin) reduce the effectiveness of combination oral contraceptives. Earlier studies suggesting this were not well-supported.

The exception is rifampin and related rifamycin antibiotics — these are genuine, major interactions that require backup contraception. For all other standard antibiotics, no additional contraceptive precautions are needed with Low-Ogestrel.

How Low-Ogestrel Affects Other Medications

Low-Ogestrel can also change how your body processes other drugs:

Lamotrigine (Lamictal) — Low-Ogestrel can significantly decrease lamotrigine levels in the blood, potentially causing breakthrough seizures in people with epilepsy who rely on it for seizure control. This is a critical interaction — always discuss with your neurologist before starting or stopping Low-Ogestrel.

Theophylline — Used for asthma. Estrogens can inhibit theophylline metabolism, increasing theophylline levels and potentially causing toxicity. Monitor theophylline levels if adding or stopping Low-Ogestrel.

Cyclosporine — Used in organ transplant and autoimmune conditions. Estrogens may increase cyclosporine levels. Monitor levels when starting or stopping COCs.

Selegiline — MAO inhibitor for Parkinson's. Estrogens may increase selegiline blood levels; avoid combination when possible.

Food and Supplement Interactions

St. John's Wort (also listed above) — The most significant supplement interaction. Avoid while taking Low-Ogestrel.

Grapefruit juice — May moderately increase ethinyl estradiol levels via CYP3A4 inhibition in the gut wall. The clinical significance is generally minor, but high grapefruit consumption is worth mentioning to your provider.

Soy isoflavone supplements — High doses of soy isoflavones may have mild estrogenic activity; discuss with your provider if taking high-dose soy supplements.

What to Tell Your Doctor and Pharmacist

Before starting Low-Ogestrel, give your prescriber a complete list of everything you take, including:

All prescription medications (especially seizure medications, HIV drugs, TB antibiotics)

Over-the-counter medications (especially NSAIDs, acetaminophen taken regularly)

All vitamins and supplements (especially St. John's Wort, soy isoflavones)

Any hepatitis C treatments

For more information on side effects to watch for, see our guide: Low-Ogestrel Side Effects: What to Expect and When to Call Your Doctor.

If you need help finding Low-Ogestrel in stock near you, visit medfinder.com.