Nurtec (rimegepant) has three main categories of drug interactions: medications that raise its levels dangerously high, medications that make it stop working, and a handful of heart and immune drugs that require extra spacing between doses. The interactions are well-documented in FDA prescribing information, and most come down to how your body processes the drug through your liver and gut.
Strong CYP3A4 Inhibitors: The Most Serious Interaction
Your liver breaks down Nurtec using a specific enzyme pathway called CYP3A4. Drugs that block this pathway cause Nurtec to build up in your bloodstream to potentially unsafe levels. In clinical testing, taking Nurtec alongside the antifungal itraconazole (a strong CYP3A4 inhibitor) increased overall drug exposure by four times and peak blood levels by about 50%. That is a dramatic jump from a single standard dose.
The FDA recommends avoiding Nurtec entirely with strong CYP3A4 inhibitors. Common medications in this category include:
- Antifungals: itraconazole, ketoconazole, posaconazole, voriconazole
- Certain antibiotics: clarithromycin, telithromycin
- HIV medications: ritonavir, cobicistat, and several other protease inhibitors
- Cancer drugs: ceritinib, idelalisib
If you’re on any of these medications long-term, Nurtec is generally not a good fit, and your prescriber would likely choose a different migraine treatment.
Moderate CYP3A4 Inhibitors: Spacing Required
Moderate inhibitors of the same liver enzyme don’t raise Nurtec levels as dramatically, but they still create a meaningful increase. The FDA guidance for these drugs is to avoid taking another dose of Nurtec within 48 hours. This matters most if you use Nurtec every other day for migraine prevention, since you’d need to extend the gap between doses.
Common moderate CYP3A4 inhibitors include fluconazole (a widely prescribed antifungal), erythromycin, diltiazem, verapamil, and certain HIV treatments like atazanavir. Grapefruit and grapefruit juice also fall into this category, which is covered below.
Drugs That Make Nurtec Less Effective
The opposite problem happens with drugs that speed up the CYP3A4 enzyme. These cause your body to break down Nurtec too quickly, so not enough of the drug stays in your system to treat or prevent migraines. In a clinical study, the antibiotic rifampin reduced Nurtec’s overall exposure by 80% and its peak concentration by 64%. At that level, the drug is essentially rendered useless.
The FDA says to avoid taking Nurtec with strong or moderate CYP3A4 inducers. These include:
- Seizure medications: carbamazepine, phenytoin, phenobarbital
- Antibiotics: rifampin
- HIV medications: efavirenz
- Supplements: St. John’s wort (covered in more detail below)
There is no dose adjustment that fixes this. These drugs reduce Nurtec levels so substantially that taking a higher dose is not recommended. If you need one of these medications, a different migraine treatment is the practical answer.
Heart and Immune Drugs That Affect Drug Transport
Beyond liver enzymes, Nurtec also interacts with a separate system: protein pumps in your gut called P-glycoprotein (P-gp) transporters. These pumps normally help push drugs back out of your cells, keeping blood levels in check. Medications that block these pumps allow more Nurtec to enter your bloodstream. Clinical testing with cyclosporine and quinidine each showed roughly a 60% increase in Nurtec exposure.
The FDA lists five specific potent P-gp inhibitors that require the 48-hour spacing rule:
- Amiodarone (used for irregular heart rhythms)
- Cyclosporine (an immune-suppressing drug for transplant patients and autoimmune conditions)
- Lapatinib (a cancer treatment)
- Quinidine (another heart rhythm drug)
- Ranolazine (used for chronic chest pain)
If you take any of these, you can still use Nurtec, but you need to wait at least 48 hours before your next dose. This is especially relevant for people taking Nurtec on an every-other-day prevention schedule, since the normal dosing interval is already 48 hours and any extra dose within that window would be too soon.
Grapefruit and St. John’s Wort
Two common over-the-counter items interact with Nurtec in opposite directions. Grapefruit and grapefruit juice inhibit CYP3A4, raising Nurtec levels in a way similar to the moderate inhibitors listed above. If you drink grapefruit juice or eat grapefruit around the time you take Nurtec, the recommendation is to skip your next dose for at least 48 hours. An occasional small glass is unlikely to cause problems, but regular large amounts should be avoided.
St. John’s wort, a popular herbal supplement for mood, is a well-known CYP3A4 inducer. It speeds up Nurtec’s breakdown and can significantly reduce its effectiveness, just as prescription inducers like rifampin do. The FDA recommends avoiding the combination altogether. If you use St. John’s wort for depression or anxiety, mention it when discussing migraine treatment options.
Medications That Are Safe to Combine
Many people with migraines wonder whether they can take Nurtec alongside their existing acute treatments. The FDA label specifically addresses sumatriptan, the most commonly prescribed triptan. No clinically relevant changes in blood pressure or drug levels were observed when the two were given together. NSAIDs like ibuprofen are not listed as an interaction in the prescribing information either.
A more nuanced question is whether Nurtec can be used alongside injectable CGRP antibodies like erenumab (Aimovig), fremanezumab (Ajovy), or galcanezumab (Emgality). These injectable drugs are used for migraine prevention and target the same pain signaling pathway as Nurtec. Some headache specialists do prescribe this combination, using the injectable for prevention and Nurtec for breakthrough attacks. Small studies reviewing this practice have not reported significant adverse effects, though the data is still limited. One theoretical concern is that doubling up on this pathway could affect blood pressure in people who already have cardiovascular risk factors, but no direct evidence of that has emerged so far.
How to Check Your Medications
The pattern with Nurtec interactions is straightforward: drugs that slow your liver’s CYP3A4 enzyme raise Nurtec levels, drugs that speed it up make Nurtec useless, and drugs that block P-gp pumps in your gut modestly increase absorption. If you take multiple prescription medications, the simplest approach is to bring a complete medication list (including supplements like St. John’s wort) to your pharmacist and ask them to run an interaction check before filling your Nurtec prescription. Pharmacists have software that flags these interactions automatically, and they can identify whether your specific combination requires dose spacing, a different migraine drug, or no changes at all.