Drug & supplement interaction

Hydrazine Sulfate + Selegiline

Selegiline brand names: Carbex, Eldepryl, Emsam, Zelapar.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Hydrazine Sulfate has a moderate interaction with Selegiline. Theoretically, concomitant use with other MAOIs might increase the effects and adverse effects associated with MAOIs.

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

Hydrazine Sulfate and Selegiline

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

Moderate

MONOAMINE OXIDASE INHIBITORS (MAOIs)

Why this applies to Selegiline

Selegiline falls under MONOAMINE OXIDASE INHIBITORS (MAOIs) — the group Hydrazine Sulfate interacts with.

Theoretically, concomitant use with other MAOIs might increase the effects and adverse effects associated with MAOIs.
Medications with hydrazine chemical moieties (e.g., phenelzine) are known to inhibit monoamine oxidase. Theoretically, hydrazine sulfate acts as an MAOI.
Severity Moderate Likelihood Possible Evidence D

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 concern with pairing these two. Selegiline is itself an MAO inhibitor (specifically an MAO-B inhibitor for Parkinson's). Hydrazine sulfate contains a hydrazine chemical group, and other hydrazine drugs like phenelzine are known to block monoamine oxidase too. So in theory, taking them together could stack two MAO-blocking effects on top of each other, which can push blood pressure too high and raise the risk of dangerous reactions, including a serious spike in blood pressure or, with certain foods or other serotonin drugs, an excess of brain chemicals.

I want to be honest about the strength of this: it is theoretical, based on how the chemicals behave, not on solid studies. That said, hydrazine sulfate is a risky, unapproved substance with real nerve and liver toxicity, and I would not combine it with selegiline. Please run this by your doctor or pharmacist first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Freese, E., Sklarow, S., and Freese, E. B. DNA damage caused by antidepressant hydrazines and related drugs. Mutat.Res 1968;5(3):343-348. PubMed

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

Hydrazine Sulfate Also Interacts With Other Medications

Hydrazine Sulfate has 97 moderate known drug interactions in our database — the Selegiline one above is one of them. If you take anything else, check it against the full list below.

Moderate 97 No known interaction 2,733 (incl. Selegiline)
Taking anything else?

Check Another of Your Medications Against Hydrazine Sulfate

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

Everything else you take

See Every Supplement That Interacts With Selegiline

This page covers Hydrazine Sulfate only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Selegiline page lists 102 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Bitter Orange (major), Brewer's Yeast (major) and Cowhage (major).

By severity: 14 major · 75 moderate · 13 minor.

Open the Selegiline interaction page

How much people look this up

Where Hydrazine Sulfate and Selegiline 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 Hydrazine Sulfate
Top half

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

29 days ago today
Medication Selegiline
Steady interest

#2,223 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 Hydrazine Sulfate

What is Hydrazine Sulfate?

  • Cancer-related weight loss (cachexia)
  • Cancer treatment (unproven)
  • Appetite stimulation
  • Improving quality of life in advanced illness

Hydrazine sulfate is a synthetic industrial chemical that was promoted as an alternative cancer treatment, but well-designed clinical trials found it does not help people with cancer live longer or feel better. It carries real risks, including serious nerve and liver toxicity, and is not approved or recommended for any medical use. Talk with your doctor or pharmacist before considering it.

Read the full Hydrazine Sulfate monograph & all interactions
Medication

About Selegiline

What Is Selegiline Used For?

Brand names: Carbex, Eldepryl, Emsam, Zelapar

Selegiline is used as an add-on treatment for people with Parkinson's disease who are already taking levodopa/carbidopa but are finding that the medication's effects are wearing off or becoming less reliable. It is not used alone — it only works as part of a combination approach.

In clinical studies, adding selegiline helped reduce the amount of daily levodopa needed, cut down on "off" time (periods when symptoms break through), and improved things like tremor, speech, movement, and overall daily function.

See full Selegiline drug information
Keep checking

Other Drugs & Hydrazine Sulfate

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

0Major
97Moderate
0Minor
2,732No known interaction
97 Moderate 2,732 No interaction
Moderate

97 interactions

Showing 60 of 97 moderate interactions — see all 97 on the Hydrazine Sulfate page.

No interaction 2,732 drugs checked — show the list

We also checked Hydrazine Sulfate against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,732 medications checked with no known interaction — see the full Hydrazine Sulfate list.

See the full Hydrazine Sulfate interactions page
See every supplement checked against Selegiline, ranked by severity
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

Keep exploring
Hydrazine Sulfate monograph › Uses, safety, and every drug interaction in one place Selegiline supplement interactions › Every supplement checked against Selegiline, ranked by severity Selegiline drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Hydrazine Sulfate and Selegiline Together: Common Questions

Can you take Hydrazine Sulfate with Selegiline?
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 Hydrazine Sulfate and Selegiline 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 Selegiline and Hydrazine Sulfate?

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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.