Drug & supplement interaction

Hoodia + Phenoxybenzamine

Phenoxybenzamine brand name: Dibenzyline.

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

Hoodia has a moderate interaction with Phenoxybenzamine. Clinical research shows that hoodia can increase blood pressure.

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

Hoodia and Phenoxybenzamine

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

Moderate

ANTIHYPERTENSIVE DRUGS

Why this applies to Phenoxybenzamine

Phenoxybenzamine falls under ANTIHYPERTENSIVE DRUGS — the group Hoodia interacts with.

Clinical research shows that hoodia can increase blood pressure. Theoretically, concomitant use of hoodia with antihypertensive drugs might decrease the effectiveness of the antihypertensive drugs and increase the risk of hypertension. Some antihypertensive drugs include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDiuril), furosemide (Lasix), and many others.
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. Phenoxybenzamine works by blocking alpha receptors to relax your blood vessels and tame the blood pressure spikes and sweating that come with pheochromocytoma. Hoodia, on the other hand, has been shown in some research to nudge blood pressure upward. So in theory, hoodia could push against what your medication is trying to do, making it harder to keep those episodes under control.

I want to be honest about how solid this is: this is a theoretical interaction based on how each one behaves, not hard proof in people taking them together. Phenoxybenzamine isn't a prodrug, so this isn't about how it's broken down, it's simply opposing effects on blood pressure. Given how serious pheochromocytoma can be, please check with your doctor or pharmacist before trying hoodia.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Blom WAM, Abrahamse SL, Bradford R, et al. Effects of 15-d repeated consumption of Hoodia gordonii purified extract on safety, ad libitum energy intake, and body weight in healthy, overweight women: a randomized controlled trial. Am J Clin Nutr 2011;94(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

Hoodia Also Interacts With Other Medications

Hoodia has 261 moderate known drug interactions in our database — the Phenoxybenzamine one above is one of them. If you take anything else, check it against the full list below.

Moderate 261 No known interaction 2,569 (incl. Phenoxybenzamine)
Taking anything else?

Check Another of Your Medications Against Hoodia

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

Everything else you take

See Every Supplement That Interacts With Phenoxybenzamine

This page covers Hoodia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phenoxybenzamine page lists 137 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), Tyramine (major) and Adrafinil (moderate).

By severity: 4 major · 112 moderate · 21 minor.

From our pharmacist’s overview on the Phenoxybenzamine page

“Phenoxybenzamine (Dibenzyline) is usually prescribed for pheochromocytoma, an adrenal tumor that sends blood pressure surging, often to steady a patient in the weeks before surgery, so keeping pressure in a narrow band is the entire goal of treatment. That makes this a list to treat carefully rather than skim.”

Reviewed by 2 · Jul 18, 2026

Open the Phenoxybenzamine interaction page

One more smart check

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

We hold 283 real supplement products containing Hoodia, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hoodia. Your product may carry other ingredients that interact with Phenoxybenzamine too, on top of Hoodia — 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 Hoodia and Phenoxybenzamine 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 Hoodia
Top 25%

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

29 days ago today
Medication Phenoxybenzamine
Top 25%

#647 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 Hoodia

What is Hoodia?

Hoodia
  • Appetite suppression
  • Weight loss
  • Reducing food cravings
  • Traditional use for hunger and thirst on long journeys

Hoodia is a succulent plant from southern Africa that is marketed as an appetite suppressant for weight loss, but solid human evidence that it actually works is lacking. The few quality studies done have not shown meaningful weight loss, and some products on the market may not even contain real hoodia. Talk with your pharmacist or doctor before trying it, and avoid it if you are pregnant or breastfeeding.

Read the full Hoodia monograph & all interactions
Medication

About Phenoxybenzamine

What Is Phenoxybenzamine Used For?

Brand name: Dibenzyline

Phenoxybenzamine hydrochloride capsules are used to treat pheochromocytoma — a rare tumor of the adrenal gland that releases large bursts of stress hormones, causing dangerous spikes in blood pressure and heavy sweating. The capsules help keep those episodes under control.

If the heart rate becomes too fast during treatment, a doctor may also prescribe a beta-blocker alongside phenoxybenzamine.

See full Phenoxybenzamine drug information
Keep checking

Other Drugs & Hoodia

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

0Major
261Moderate
0Minor
2,568No known interaction
261 Moderate 2,568 No interaction
Moderate

261 interactions

Showing 60 of 261 moderate interactions — see all 261 on the Hoodia page.

No interaction 2,568 drugs checked — show the list

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

Showing the 60 most looked-up of 2,568 medications checked with no known interaction — see the full Hoodia list.

See the full Hoodia interactions page
See every supplement checked against Phenoxybenzamine, 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
Hoodia monograph › Uses, safety, and every drug interaction in one place Phenoxybenzamine supplement interactions › Every supplement checked against Phenoxybenzamine, ranked by severity Phenoxybenzamine 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 Hoodia and Phenoxybenzamine Together: Common Questions

Can you take Hoodia with Phenoxybenzamine?
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 Hoodia and Phenoxybenzamine 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 Phenoxybenzamine and Hoodia?

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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.