Drug & supplement interaction

Umckaloabo + Phenprocoumon

Phenprocoumon brand name: Liquamar.

Minor Interaction
The bottom line Minor

Umckaloabo has a minor interaction with Phenprocoumon. Theoretically, Pelargonium sidoides might increase the risk of bleeding when taken with anticoagulant and antiplatelet drugs.

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

Umckaloabo and Phenprocoumon

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

Minor

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Phenprocoumon

Phenprocoumon falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Umckaloabo interacts with.

Theoretically, Pelargonium sidoides might increase the risk of bleeding when taken with anticoagulant and antiplatelet drugs.
Pelargonium sidoides contains coumarin, which may reduce platelet aggregation. However, in animal models, Pelargonium sidoides extract does not appear to inhibit coagulation or interact with warfarin. This interaction has not been documented in humans.
Severity Minor Likelihood Unlikely Evidence D

Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans..

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

Here is the short version: phenprocoumon is a strong blood thinner, very similar to warfarin, and it has a narrow safety window where small shifts can tip you toward too much or too little effect. Umckaloabo (Pelargonium sidoides) contains coumarin-type compounds, and on paper that raises a worry that it could nudge your blood toward thinner, slightly raising bleeding risk.

In real life, though, this concern is mostly theoretical. Animal studies did not show it interfering with clotting or with warfarin, and it has never been reported as a problem in people. Still, because phenprocoumon is so dose-sensitive, I would not start this supplement without telling your doctor first. Watch for easy bruising, nosebleeds, or bleeding gums, and keep up your regular INR checks.

References
  1. Kolodziej H, Kayser O, Radtke OA, et al. Pharmacological profile of extracts of Pelargonium sidoides and their constituents. Phytomedicine 2003;10 Suppl 4:18-24. PubMed
  2. Koch E, Biber A. Treatment of rats with the Pelargonium sidoides extract EPs 7630 has no effect on blood coagulation parameters or on the pharmacokinetics of warfarin. Phytomedicine 2007;14 Suppl 6:40-5. 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

Umckaloabo Also Interacts With Other Medications

Umckaloabo has 121 moderate, 119 minor known drug interactions in our database — the Phenprocoumon 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 Umckaloabo

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

Everything else you take

See Every Supplement That Interacts With Phenprocoumon

This page covers Umckaloabo only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phenprocoumon page lists 219 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Danshen (major), Piracetam (major), St. John's Wort (major) and Aconite (moderate).

By severity: 4 major · 190 moderate · 25 minor.

From our pharmacist’s overview on the Phenprocoumon page

“Phenprocoumon (Liquamar) is a blood thinner in the coumarin family, a close cousin of warfarin, and small shifts in its blood level can tip you toward a clot or a bleed, so I treat this list with genuine care. Almost everything on it pushes the drug's effect further, layering extra bleeding risk on blood that is already thinned.”

Reviewed by 2 · Jul 18, 2026

Open the Phenprocoumon interaction page

One more smart check

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

We hold 77 real supplement products containing Umckaloabo, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Umckaloabo. Your product may carry other ingredients that interact with Phenprocoumon too, on top of Umckaloabo — 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 Umckaloabo and Phenprocoumon 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 Umckaloabo
Steady interest

#1,048 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Phenprocoumon
Top half

#773 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 Umckaloabo

What is Umckaloabo?

Umckaloabo
  • Acute bronchitis
  • Common cold
  • Sinusitis
  • Sore throat
  • Upper respiratory infections

Umckaloabo is a root extract from a South African geranium that is most studied for short-term relief of acute bronchitis and other respiratory infections. Some clinical research suggests it may help symptoms resolve a bit faster, but the quality of evidence is mixed and it is not a cure. Talk to your pharmacist or doctor before using it, especially if you are pregnant, breastfeeding, or have a chronic illness.

Read the full Umckaloabo monograph & all interactions
Keep checking

Other Drugs & Umckaloabo

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

0Major
121Moderate
119Minor
2,589No known interaction
Moderate

121 interactions

Showing 60 of 121 moderate interactions — see all 121 on the Umckaloabo page.

Minor

119 interactions

Showing 60 of 119 minor interactions — see all 119 on the Umckaloabo page.

No interaction 2,589 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 Umckaloabo and Phenprocoumon Together: Common Questions

Can you take Umckaloabo with Phenprocoumon?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Umckaloabo and Phenprocoumon interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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.