Drug & supplement interaction

Melatonin + Emapalumab-Lzsg

Emapalumab-Lzsg brand name: Gamifant.

Moderate Interaction
The bottom line Moderate

Melatonin has a moderate interaction with Emapalumab-Lzsg. Theoretically, melatonin might interfere with immunosuppressive therapy.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
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Interaction report

Melatonin and Emapalumab-Lzsg

Here is the interaction we found between these two, with the evidence behind it.

Moderate

IMMUNOSUPPRESSANTS

Why this applies to Emapalumab-Lzsg

Emapalumab-Lzsg falls under IMMUNOSUPPRESSANTS — the group Melatonin interacts with.

Theoretically, melatonin might interfere with immunosuppressive therapy.
Melatonin can stimulate immune function. Theoretically, melatonin might interfere with immunosuppressive therapy.
Severity Moderate Likelihood Possible Evidence B

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the idea behind this pairing. Gamifant (emapalumab) is a monoclonal antibody that calms an overactive immune system in primary HLH by blocking an inflammatory protein called interferon-gamma. Melatonin, on the other hand, can gently nudge the immune system in the opposite direction (it may stimulate immune activity). So the theoretical worry is that melatonin could work against what Gamifant is trying to do, possibly making the treatment less effective.

I want to be honest about the evidence here: this is largely theoretical and based on weak data, not on solid studies in people taking this exact drug. Given that HLH is a serious, closely monitored condition, please don't add melatonin on your own. Run it by your specialist or pharmacist first, and they can weigh whether it's reasonable for you.

References
  1. Lissoni P, Barni S, Mandala M, et al. Decreased toxicity and increased efficacy of cancer chemotherapy using the pineal hormone melatonin in metastatic solic tumor patients with poor clinical status. Eur J Cancer 1999;35:1688-92.

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Melatonin Also Interacts With Other Medications

Melatonin has 1,115 moderate, 345 minor known drug interactions in our database — the Emapalumab-Lzsg one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Melatonin

Covers the 2,830 medications we’ve checked against Melatonin. Pick one to open its full report.

From our Q&A

Questions About Melatonin or Emapalumab-Lzsg

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Melatonin or Emapalumab-Lzsg, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Emapalumab-Lzsg

This page covers Melatonin only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Emapalumab-Lzsg page lists 53 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Active Hexose Correlated Compound (ahcc) (moderate), Alfalfa (moderate), American Ginseng (moderate), Andrographis (moderate) and Ashwagandha (moderate).

By severity: 52 moderate · 1 minor.

From our pharmacist’s overview on the Emapalumab-Lzsg page

“Emapalumab-lzsg (Gamifant) quiets an immune system that has turned dangerously overactive in a rare condition called hemophagocytic lymphohistiocytosis. All 53 supplement interactions on file share a single theme, a possible boost to immune activity that could work against the drug.”

Reviewed by 2 · Jul 18, 2026

Open the Emapalumab-Lzsg interaction page

One more smart check

Taking Melatonin as Part of a Dietary Supplement Product? Check It for Interactions

We hold 2,885 real supplement products containing Melatonin, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Melatonin. Your product may carry other ingredients that interact with Emapalumab-Lzsg too, on top of Melatonin — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Melatonin and Emapalumab-Lzsg Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Melatonin
Top 5%

#55 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Emapalumab-Lzsg
Steady interest

#2,181 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Melatonin

What is Melatonin?

Melatonin
  • Trouble falling asleep (insomnia)
  • Jet lag
  • Delayed sleep phase syndrome
  • Non-24-hour sleep-wake disorder
  • Shift-work sleep problems
  • Sleep problems in some children with conditions like autism or ADHD

Melatonin is a hormone your body makes naturally to help control your sleep-wake cycle, and the supplement form is widely used to help with sleep timing problems and jet lag. The evidence is strongest for certain circadian (body-clock) disorders and is more mixed for everyday insomnia. It is generally well tolerated for short-term use, but talk with your pharmacist or doctor before starting, especially for children or during pregnancy.

Read the full Melatonin monograph & all interactions
Medication

About Emapalumab-lzsg Injection

What Is Emapalumab-lzsg Injection Used For?

Brand name: Gamifant

Gamifant is used to treat primary hemophagocytic lymphohistiocytosis (HLH) — a rare, life-threatening condition where the immune system becomes dangerously overactivated — in adults and children whose disease has not responded to, has come back during, or has progressed on standard HLH therapy, or who cannot tolerate it.

Gamifant is also used for HLH/macrophage activation syndrome (MAS) in adults and children with known or suspected Still's disease, including systemic Juvenile Idiopathic Arthritis (sJIA), when glucocorticoids (steroid medicines) have not worked well enough, cannot be tolerated, or when MAS keeps coming back.

See full Emapalumab-lzsg Injection drug information
Keep checking

Other Drugs & Melatonin

Browse every other medication we’ve checked against Melatonin — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
1,115Moderate
345Minor
1,369No known interaction
Moderate

1,115 interactions

Showing 60 of 1,115 moderate interactions — see all 1,115 on the Melatonin page.

Minor

345 interactions

Showing 60 of 345 minor interactions — see all 345 on the Melatonin page.

No interaction 1,369 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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Pharmacist Counseling Corner

Taking Melatonin and Emapalumab-Lzsg Together: Common Questions

Can you take Melatonin with Emapalumab-Lzsg?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Melatonin and Emapalumab-Lzsg interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Emapalumab-Lzsg and Melatonin?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.