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

One of the advantages of Nemluvio (nemolizumab-ilto) as a targeted biologic is its relatively limited drug interaction profile. Because it works by blocking a specific receptor (IL-31RA) rather than broadly affecting metabolism, it doesn't interact with most medications the way many drugs do. That said, there are important interactions and precautions every patient and provider needs to know before starting or continuing Nemluvio.

The Most Important Interaction: Live Vaccines

The most clinically significant interaction for Nemluvio is with live vaccines. Nemluvio may reduce the efficacy of live virus vaccines because its immunomodulatory effects could interfere with the immune response these vaccines depend on.

What this means in practice:

Complete all recommended live vaccines BEFORE starting Nemluvio treatment

Do NOT receive any live vaccines while on Nemluvio treatment

Inactivated (killed) and non-live vaccines (flu shots, COVID-19 vaccines, hepatitis B, pneumococcal, etc.) are generally safe to take while on Nemluvio

Live vaccines to avoid during Nemluvio treatment include:

MMR (measles, mumps, rubella)

Varicella (chickenpox) vaccine

Zoster (shingles) live vaccine (Zostavax) — note: the non-live Shingrix version is safe

Live attenuated influenza vaccine (nasal spray flu vaccine)

Yellow fever vaccine

BCG vaccine

CYP450 Drug Interactions: Narrow Therapeutic Index Medications

Cytokines like IL-31 can influence the activity of CYP450 liver enzymes — the enzymes that metabolize many medications. Because Nemluvio inhibits IL-31 signaling, it may affect CYP450 enzyme activity and thereby alter the levels of drugs processed by those enzymes.

This is a moderate concern for medications with a narrow therapeutic index — drugs where small changes in blood concentration can lead to toxicity or loss of efficacy. When you start or stop Nemluvio, your doctor may need to monitor levels or adjust the dose of these medications:

Warfarin (Coumadin) — a blood thinner; INR should be monitored when starting or stopping Nemluvio

Cyclosporine — an immunosuppressant; blood levels should be checked upon initiation/discontinuation of Nemluvio

Other CYP450 substrates with narrow therapeutic windows (e.g., certain antiepileptics, digoxin) — discuss with your prescribing doctor

Medications That Are Safe to Take With Nemluvio

Nemluvio is specifically approved for use in combination with:

Topical corticosteroids (TCS) — routinely used alongside Nemluvio for atopic dermatitis

Topical calcineurin inhibitors (TCI) — such as tacrolimus and pimecrolimus; used alongside Nemluvio for AD

General medications without CYP450 concerns (most common over-the-counter drugs, most antihypertensives, most antidepressants) are not expected to interact meaningfully with Nemluvio.

What to Tell Your Doctor Before Starting Nemluvio

Before starting Nemluvio, give your doctor a complete medication list, including:

All prescription medications (especially anticoagulants, antiepileptics, immunosuppressants, and transplant medications)

Over-the-counter medications and supplements

Upcoming travel plans requiring live vaccines

Any recent vaccinations (live vaccines in the past few weeks may require a waiting period before starting Nemluvio)

Pregnancy or breastfeeding status (limited data; discuss risks and benefits with your doctor)

For information on Nemluvio side effects beyond interactions, read our guide on Nemluvio side effects. Once you're ready to fill your prescription, medfinder can help identify which specialty pharmacies near you can dispense it.