Drug & supplement interaction

K2/spice + Dexmedetomidine

Dexmedetomidine brand names: Precedex, Igalmi.

Moderate Interaction
The bottom line Moderate

K2/spice has a moderate interaction with Dexmedetomidine. Theoretically, K2/spice might have an additive effect with drugs that prolong the QT interval and increase the risk of ventricular arrhythmias.

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

K2/spice and Dexmedetomidine

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

Moderate

QT INTERVAL-PROLONGING DRUGS

Why this applies to Dexmedetomidine

Dexmedetomidine falls under QT INTERVAL-PROLONGING DRUGS — the group K2/spice interacts with.

Theoretically, K2/spice might have an additive effect with drugs that prolong the QT interval and increase the risk of ventricular arrhythmias.
There have been numerous cases of increased QT and corrected QT intervals in patients using K2/spice.
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

First, the big picture: K2/Spice isn't a real herbal supplement. It's plant material sprayed with man-made synthetic cannabinoids, and it's genuinely dangerous. People have ended up with seizures, racing or irregular heartbeats, psychosis, and some have died. There's no safe dose, so it should not be used at all.

With dexmedetomidine (Precedex, Igalmi), the specific concern is the heart's electrical rhythm. Both this medicine and K2/Spice can stretch out the QT interval, and combining them may add up and raise the risk of a dangerous arrhythmia. Dexmedetomidine is given in hospitals for sedation and already tends to slow your heart rate and drop your blood pressure, so adding an unpredictable street product on top is risky. This is based on case reports, not strong studies, but please don't combine them. Talk with your doctor or pharmacist.

References
  1. Ahmed T, Khan A, See VY, Robinson S. Cardiac arrest associated with synthetic cannabinoid use and acquired prolonged QTc interval: A case report and review of literature. HeartRhythm Case Rep. 2020;6(5):283-286. PubMed
  2. Yildiz SS, Sutasir MN, Sigirci S, et al. Acute effects of synthetic cannabinoids on ventricular repolarization parameters. Turk Kardiyol Dern Ars. 2019;47(5):384-390.

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

K2/spice Also Interacts With Other Medications

K2/spice has 207 moderate known drug interactions in our database — the Dexmedetomidine 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 K2/spice

Covers the 2,830 medications we’ve checked against K2/spice. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Dexmedetomidine

This page covers K2/spice only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dexmedetomidine page lists 108 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), American Hellebore (major), Arsenic (major) and Beer (major).

By severity: 13 major · 80 moderate · 15 minor.

From our pharmacist’s overview on the Dexmedetomidine page

“Dexmedetomidine (Precedex, Igalmi) is itself a sedative, used for procedural sedation and to calm acute agitation, so the 108 supplements and herbs on this list deserve real vigilance rather than a shrug. Most of them, 78 in all, deepen its sedative effect; the major entries here include alcohol and kava, which can push ordinary drowsi…”

Reviewed by 2 · Jul 18, 2026

Open the Dexmedetomidine interaction page

How much people look this up

Where K2/spice and Dexmedetomidine 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 K2/spice
Steady interest

#1,337 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Dexmedetomidine
Steady interest

#1,991 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 K2/spice

What is K2/spice?

  • Recreational drug ('legal high')
  • Marijuana substitute
  • Mood or perception changes
  • Sometimes used to avoid drug testing

K2/Spice is NOT a herbal supplement — it is plant material sprayed with man-made synthetic cannabinoid chemicals. It is dangerous, unpredictable, and has caused seizures, heart problems, psychosis, and deaths, so it should not be used.

Read the full K2/spice monograph & all interactions
Keep checking

Other Drugs & K2/spice

Browse every other medication we’ve checked against K2/spice — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
207Moderate
0Minor
2,622No known interaction
Moderate

207 interactions

Showing 60 of 207 moderate interactions — see all 207 on the K2/spice page.

No interaction 2,622 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 K2/spice and Dexmedetomidine Together: Common Questions

Can you take K2/spice with Dexmedetomidine?
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 K2/spice and Dexmedetomidine 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.