Drug & supplement interaction

Isopropylnorsynephrine + Mannitol

Mannitol brand names: Osmitrol, Bronchitol.

Moderate Interaction
The bottom line Moderate

Isopropylnorsynephrine has a moderate interaction with Mannitol. Theoretically, isopropylnorsynephrine might decrease the effects of antihypertensive drugs.

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

Isopropylnorsynephrine and Mannitol

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

Moderate

ANTIHYPERTENSIVE DRUGS

Why this applies to Mannitol

Mannitol falls under ANTIHYPERTENSIVE DRUGS — the group Isopropylnorsynephrine interacts with.

Theoretically, isopropylnorsynephrine might decrease the effects of antihypertensive drugs.
In vitro research shows that isopropylnorsynephrine is a highly selective, direct-acting beta-adrenergic receptor agonist with positive chronotropic effects, and hypertension has been reported in patients taking combination products containing isopropylnorsynephrine and other stimulants.
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 honest picture: mannitol isn't a typical blood pressure pill. It's an osmotic diuretic, used in hospitals to pull fluid out (for example to reduce pressure in the brain or eyes), and some forms are inhaled for cystic fibrosis. The interaction on file is grouped under antihypertensive drugs, and the idea is that a stimulant like isopropylnorsynephrine, which can raise heart rate and blood pressure, might work against medicines meant to lower it.

For mannitol specifically, this overlap is weak and mostly theoretical, based on lab and animal data, not real patient studies. Still, a stimulant that bumps up blood pressure isn't ideal alongside any fluid-shifting hospital treatment. Please run any supplement like this past your doctor or pharmacist first.

References
  1. Venhuis B, Keizers P, van Riel A, de Kaste D. A cocktail of synthetic stimulants found in a dietary supplement associated with serious adverse events. Drug Test Anal. 2014 Jun;6(6):578-81. doi: 10.1002/dta.1664. Epub 2014 May 6. PubMed
  2. Anderson WG. The sympathomimetic activity of N-isopropyloctopamine in vitro. J Pharmacol Exp Ther 1983;225(3):553-8. DOI

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

Isopropylnorsynephrine Also Interacts With Other Medications

Isopropylnorsynephrine has 343 moderate known drug interactions in our database — the Mannitol 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 Isopropylnorsynephrine

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

Everything else you take

See Every Supplement That Interacts With Mannitol

This page covers Isopropylnorsynephrine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Mannitol page lists 200 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Lithium (major) and Oleander (major).

By severity: 7 major · 169 moderate · 24 minor.

From our pharmacist’s overview on the Mannitol page

“American hellebore tops my worry list for anyone on mannitol (Osmitrol, Bronchitol), an osmotic diuretic used to draw fluid off the brain or, when inhaled, to clear mucus in cystic fibrosis. The plant's alkaloids drop blood pressure and slow the heart, a dangerous match for a drug that already shifts fluid and pressure quickly.”

Reviewed by 2 · Jul 18, 2026

Open the Mannitol interaction page

One more smart check

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

We hold 48 real supplement products containing Isopropylnorsynephrine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Isopropylnorsynephrine. Your product may carry other ingredients that interact with Mannitol too, on top of Isopropylnorsynephrine — 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 Isopropylnorsynephrine and Mannitol 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 Isopropylnorsynephrine
Steady interest

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

29 days ago today
Medication Mannitol
Top 25%

#403 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 Isopropylnorsynephrine

What is Isopropylnorsynephrine?

  • Weight loss and fat burning
  • Pre-workout energy and stimulation
  • Topical fat reduction (creams and gels)
  • Appetite suppression
  • Athletic performance

Isopropylnorsynephrine is a synthetic stimulant chemically related to synephrine, marketed mainly in weight-loss and pre-workout supplements. It has very little human safety or effectiveness research, and as a stimulant it may raise heart rate and blood pressure, so caution is strongly advised. Talk with a pharmacist or doctor before using any product that contains it.

Read the full Isopropylnorsynephrine monograph & all interactions
Keep checking

Other Drugs & Isopropylnorsynephrine

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

0Major
343Moderate
0Minor
2,486No known interaction
Moderate

343 interactions

Showing 60 of 343 moderate interactions — see all 343 on the Isopropylnorsynephrine page.

No interaction 2,486 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 Isopropylnorsynephrine and Mannitol Together: Common Questions

Can you take Isopropylnorsynephrine with Mannitol?
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 Isopropylnorsynephrine and Mannitol 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

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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.