Drug Interactions That Can Affect Estarylla 28 Day

Estarylla 28 Day — a combination oral contraceptive containing Norgestimate and Ethinyl Estradiol — can interact with other medications, supplements, and even certain foods. Some interactions reduce the pill's effectiveness at preventing pregnancy. Others change how your body processes other drugs you're taking.

This guide covers the major and moderate interactions you need to know about, and what to tell your doctor before starting Estarylla 28 Day.

How Drug Interactions Work with Oral Contraceptives

Most drug interactions with Estarylla 28 Day happen in one of two ways:

1. Another drug speeds up how your liver breaks down the hormones. This lowers the hormone levels in your blood, potentially making the pill less effective at preventing pregnancy. These are the most concerning interactions.
2. Estarylla 28 Day changes how your body processes another drug. The estrogen and progestin in the pill can increase or decrease the levels of other medications, affecting their safety or effectiveness.

The liver enzyme system involved is called CYP3A4. Drugs that "induce" (speed up) this enzyme are the biggest concern for contraceptive failure.

Major Drug Interactions — Use Backup Contraception

These medications significantly reduce Estarylla 28 Day's effectiveness. If you take any of these, you'll likely need an alternative contraceptive method or backup protection:

Rifampin (Rifadin)

This is the most well-documented interaction with oral contraceptives. Rifampin — used to treat tuberculosis and some other infections — is a potent CYP3A4 inducer that can reduce Ethinyl Estradiol levels by up to 64%. Oral contraceptives should not be relied upon as the sole method of birth control while taking Rifampin. Your doctor should prescribe an alternative contraceptive method.

Anticonvulsants (Seizure Medications)

Several anti-seizure medications reduce oral contraceptive effectiveness:

• Phenytoin (Dilantin)
• Carbamazepine (Tegretol)
• Phenobarbital
• Topiramate (Topamax) — at doses above 200 mg/day
• Oxcarbazepine (Trileptal)
• Felbamate (Felbatol)

If you take any of these medications, talk to your neurologist and OB/GYN about contraceptive options. Non-oral methods like the hormonal IUD or copper IUD are often recommended because they aren't affected by enzyme-inducing drugs.

HIV Medications

Some HIV protease inhibitors and non-nucleoside reverse transcriptase inhibitors (NNRTIs) can have variable effects on oral contraceptive hormone levels — some increase them, some decrease them. If you're on HIV treatment, your infectious disease specialist should coordinate with your prescriber to ensure effective contraception.

St. John's Wort

This popular herbal supplement for mood support is a potent CYP3A4 inducer. It can significantly reduce the effectiveness of Estarylla 28 Day. Do not take St. John's Wort while on combination oral contraceptives. If you need support for mood symptoms, talk to your doctor about prescription options that don't interact with your birth control.

Bosentan (Tracleer)

Used to treat pulmonary arterial hypertension, Bosentan reduces oral contraceptive effectiveness. An alternative or additional contraceptive method is recommended.

Griseofulvin

This antifungal medication may reduce the effectiveness of oral contraceptives. Use backup contraception during treatment and for one month after stopping Griseofulvin.

Aprepitant (Emend) and Fosaprepitant

These anti-nausea medications, often used during chemotherapy, can reduce the effectiveness of oral contraceptives. Use backup contraception during treatment and for 28 days after your last dose.

Moderate Drug Interactions — Monitor Closely

These interactions are less likely to cause contraceptive failure but may require monitoring or dose adjustments:

Lamotrigine (Lamictal)

This is a two-way interaction and one of the most clinically important:

• Estarylla 28 Day can decrease Lamotrigine levels during the active pill weeks, potentially reducing seizure control
• During the inactive (placebo) week, Lamotrigine levels may rise, increasing the risk of side effects

If you take Lamotrigine, your neurologist may need to adjust your dose when you start or stop oral contraceptives. Do not change either medication without medical guidance.

Certain Antibiotics

The interaction between oral contraceptives and antibiotics like Ampicillin and Tetracycline has been debated for decades. Current evidence suggests the risk of reduced contraceptive effectiveness is low for most antibiotics — except Rifampin, which is a definite concern (see above).

That said, some providers still recommend backup contraception during antibiotic courses as a precaution. Follow your doctor's advice.

Thyroid Medications (Levothyroxine)

Oral contraceptives increase thyroid-binding globulin levels, which can affect thyroid hormone measurements. If you take Levothyroxine (Synthroid), your doctor may need to adjust your thyroid dose and recheck your TSH levels after starting Estarylla 28 Day.

Warfarin (Coumadin)

Oral contraceptives may reduce the anticoagulant effect of Warfarin. If you take a blood thinner, your doctor will need to monitor your INR closely. Note: having a condition that requires blood thinners may also be a contraindication for combination oral contraceptives — discuss this with your provider.

Benzodiazepines

Oral contraceptives may slow the clearance of some benzodiazepines (such as Diazepam and Alprazolam), potentially increasing their sedative effects. Your doctor should be aware if you take both.

Cyclosporine

Oral contraceptives can increase Cyclosporine blood levels, raising the risk of side effects. Monitoring is recommended if you take both.

Prednisolone

Estarylla 28 Day may increase Prednisolone levels, potentially intensifying corticosteroid side effects. Your doctor should monitor you if you're on both medications.

Acetaminophen (Tylenol)

Oral contraceptives may slightly reduce the effectiveness of Acetaminophen. This is generally not clinically significant, but it's worth knowing.

Supplements and OTC Products to Watch

• St. John's Wort — As noted above, avoid entirely while on Estarylla 28 Day
• Activated charcoal — Can bind to hormones in the gut and reduce absorption. Avoid taking it within 2 to 3 hours of your pill
• High-dose vitamin C — Some reports suggest very high doses may increase Ethinyl Estradiol levels, though evidence is limited
• Detox teas and supplements — Many contain herbal ingredients (including St. John's Wort) that may interfere with hormone levels. Check ingredients carefully

Food and Drink Interactions

Grapefruit Juice

Grapefruit juice can slightly increase Ethinyl Estradiol levels by inhibiting the CYP3A4 enzyme. An occasional glass is unlikely to cause problems, but regular large consumption could increase estrogen-related side effects (like nausea or breast tenderness).

St. John's Wort Tea

Even in tea form, St. John's Wort can reduce the effectiveness of oral contraceptives. Avoid it in all forms — capsules, tinctures, and teas.

Alcohol

Alcohol does not directly reduce the effectiveness of Estarylla 28 Day. However, heavy drinking can lead to vomiting, which may reduce hormone absorption if it occurs within a few hours of taking your pill. It can also impair your memory, making it easier to forget a dose.

What to Tell Your Doctor

Before starting Estarylla 28 Day, give your doctor a complete list of:

• All prescription medications — including seizure medications, HIV treatments, blood thinners, and thyroid drugs
• All over-the-counter medications — including pain relievers, antacids, and allergy medications
• All supplements and herbal products — especially St. John's Wort, detox products, and high-dose vitamins
• Any changes to your medications — Tell your prescriber whenever you start or stop a drug while on Estarylla 28 Day

If a new provider prescribes you a medication, always mention that you're taking an oral contraceptive. Many drug interaction risks can be managed with simple precautions — but only if your healthcare team knows about them.

Final Thoughts

Most common medications are safe to take with Estarylla 28 Day. The biggest risks come from enzyme-inducing drugs like Rifampin, certain seizure medications, and St. John's Wort — all of which can significantly reduce contraceptive effectiveness.

When in doubt, ask your pharmacist. They can check for interactions in seconds and advise you on whether backup contraception is needed.

For more about Estarylla 28 Day, explore our guides on side effects, how it works, and dosage information. And use Medfinder to find Estarylla 28 Day in stock at a pharmacy near you.