Gomekli Drug Interactions: What to Avoid and What to Tell Your Doctor

Before starting Gomekli (mirdametinib), it's essential to give your healthcare provider and pharmacist a complete list of all medications, supplements, and herbal products you take. Gomekli has known drug interactions, and some combinations can affect how well the drug works or increase the risk of serious side effects. Here's what patients need to know.

How Many Drug Interactions Does Gomekli Have?

According to available drug interaction data, Gomekli (mirdametinib) has 11 known drug interactions — 2 classified as major and 9 classified as moderate. It is also associated with 4 known disease interactions (health conditions that may affect how Gomekli is used). There may be additional interactions that are not yet fully characterized, since Gomekli is a newer drug approved in 2025.

Always bring a complete and current medication list to every appointment. Include:

All prescription medications (including other cancer drugs, heart medications, seizure medications)

Over-the-counter (OTC) medications (including pain relievers, antacids, cold medicines)

Vitamins and mineral supplements

Herbal products (including St. John's Wort, echinacea, garlic supplements, etc.)

CYP Enzyme Interactions: Why They Matter

Like many specialty drugs, Gomekli is metabolized (processed) by liver enzymes, including members of the cytochrome P450 (CYP) system. Drugs or substances that strongly affect these enzymes can alter mirdametinib levels in your body — potentially making the drug less effective or increasing side effects.

Strong CYP inducers (e.g., rifampin, carbamazepine, phenytoin, St. John's Wort): These increase the activity of enzymes that break down Gomekli, potentially lowering drug levels and reducing effectiveness.

Strong CYP inhibitors (e.g., ketoconazole, clarithromycin, grapefruit juice): These slow down the enzymes that break down Gomekli, potentially raising drug levels and increasing side effects.

Tell your doctor if you take any anticonvulsant medications (seizure drugs), antifungal agents, certain antibiotics, or HIV antivirals — as many of these are CYP inducers or inhibitors.

Interactions with Heart Medications

Because Gomekli can affect heart function (left ventricular dysfunction), the combination with other medications that also affect the heart requires careful monitoring. If you take medications for heart failure, arrhythmias, or blood pressure, be sure your NF1 specialist knows about all of them. Baseline and ongoing cardiac monitoring with echocardiograms is required for all patients on Gomekli.

Interactions with Other Cancer Drugs

If you are being treated for any other condition with another targeted therapy or cancer medication, there is potential for interactions. Gomekli should not be combined with other MEK inhibitors without physician oversight. Discuss any current or past oncology treatments with your NF1 specialist before starting Gomekli.

Disease Interactions: Health Conditions That Affect Gomekli Use

Certain pre-existing health conditions can affect how Gomekli is used or monitored:

Eye diseases: Pre-existing retinal conditions may increase risk of Gomekli's ocular side effects (RVO, RPED). Comprehensive ophthalmic assessment is required before starting therapy.

Heart disease or decreased ejection fraction: Pre-existing left ventricular dysfunction may affect eligibility or require dose modifications. Echocardiogram required before starting.

Liver impairment: No dose adjustment is required for mild or moderate liver impairment, but severe liver impairment requires caution.

Pregnancy: Gomekli can cause fetal harm. Pregnancy testing is required before starting therapy.

Herbal Supplements and St. John's Wort

St. John's Wort is a potent inducer of CYP enzymes and is known to significantly reduce blood levels of many specialty drugs — including cancer treatments. Avoid St. John's Wort while taking Gomekli. Similarly, certain other herbal supplements can interact with specialty medications. Always tell your doctor and pharmacist about any herbal products you take.

What to Tell Your Doctor Before Starting Gomekli

Before your first dose of Gomekli, make sure to discuss:

All medications (prescription, OTC, supplements, herbal products)

Any history of eye problems, retinal disease, or recent eye surgery

Any history of heart failure, cardiomyopathy, or decreased ejection fraction

Current pregnancy or plans to become pregnant; contraceptive methods

Whether you are breastfeeding (Gomekli should be avoided; advise stopping breastfeeding 1 week after last dose)

Any liver disease

For more on managing Gomekli side effects and what symptoms require immediate attention, see our companion guide on Gomekli side effects.