Drug & supplement interaction

Bitter Orange + Desvenlafaxine

Desvenlafaxine brand names: Pristiq, Khedezla.

Moderate Interaction
The bottom line Moderate

Desvenlafaxine falls into 2 drug categories that Bitter Orange can interact with; the most serious is rated moderate. Theoretically, bitter orange might have an additive effect when combined with drugs that prolong the QT interval, potentially increasing the risk of ventricular arrhythmias.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Bitter Orange and Desvenlafaxine

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Bitter Orange interacts with whole categories of medication. Desvenlafaxine falls into 2 of those categories, so it can interact with Bitter Orange in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

QT INTERVAL-PROLONGING DRUGS

1 of 2

Why this applies to Desvenlafaxine

Desvenlafaxine falls under QT INTERVAL-PROLONGING DRUGS — the group Bitter Orange interacts with.

Theoretically, bitter orange might have an additive effect when combined with drugs that prolong the QT interval, potentially increasing the risk of ventricular arrhythmias.
One case report suggests that taking bitter orange in combination with other stimulants such as caffeine might prolong the QT interval in some patients.
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 gist for Pristiq (desvenlafaxine). Bitter orange contains synephrine, a stimulant that can nudge up your heart rate and blood pressure and, in theory, affect your heart's electrical timing (called the QT interval). Desvenlafaxine is one of those medicines that can also have a small effect on QT timing, so stacking the two together might add up and raise the odds of an irregular heartbeat.

I want to be honest about how thin the evidence is here. This is mostly theoretical, with just a single case report tied to bitter orange plus other stimulants like caffeine. For most people it's a low concern, but if you have heart issues, high blood pressure, or take other stimulants, please check with your pharmacist or doctor before adding bitter orange. Don't change your desvenlafaxine on your own.

References
  1. Nasir JM, Durning SJ, Ferguson M, et al. Exercise-induced syncope associated with QT prolongation and ephedra-free Xenadrine. Mayo Clin Proc 2004;79:1059-62.. PubMed
Minor

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

2 of 2

Desvenlafaxine also falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES.

Theoretically, bitter orange might increase levels of drug metabolized by CYP2D6.
In vitro research shows that octopamine, a constituent of bitter orange, weakly inhibits CYP2D6 enzymes. This effect has not been reported in humans.
Severity Minor 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 gist for Pristiq (desvenlafaxine). Bitter orange contains a compound called octopamine that, in test-tube studies, weakly blocks an enzyme called CYP2D6. Since your body partly uses that enzyme to clear desvenlafaxine, the theory is that bitter orange could let a little more of the drug build up. In plain terms, that might mean slightly stronger effects or side effects like nausea, jitteriness, a faster heartbeat, higher blood pressure, trouble sleeping, or sweating.

I want to be honest, though: this has only been seen in lab dishes, never in real people, and it's rated a minor, weak interaction. My bigger concern is that bitter orange is itself a stimulant that raises heart rate and blood pressure, which can stack with an SNRI. If you're considering it, please run it by your pharmacist or doctor first.

References
  1. Liu Y, Santillo MF. Cytochrome P450 2D6 and 3A4 enzyme inhibition by amine stimulants in dietary supplements. Drug Test Anal. 2016;8(3-4):307-10. 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

Bitter Orange Also Interacts With Other Medications

Bitter Orange has 10 major, 875 moderate, 71 minor known drug interactions in our database — the Desvenlafaxine one above is among them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Bitter Orange

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

From our Q&A

Questions About Bitter Orange or Desvenlafaxine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Bitter Orange or Desvenlafaxine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Desvenlafaxine

This page covers Bitter Orange only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Desvenlafaxine page lists 109 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Arsenic (major), Cesium (major) and Ephedra (major).

By severity: 8 major · 81 moderate · 20 minor.

From our pharmacist’s overview on the Desvenlafaxine page

“Plenty of people taking desvenlafaxine (Pristiq, Khedezla) for depression also shop the supplement aisle for mood support, and that is exactly where this list bites hardest. Eight of the 109 entries rate major, which puts it firmly in the be-careful column.”

Reviewed by 2 · Jul 18, 2026

Open the Desvenlafaxine interaction page

One more smart check

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

We hold 1,000 real supplement products containing Bitter Orange, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Bitter Orange. Your product may carry other ingredients that interact with Desvenlafaxine too, on top of Bitter Orange — 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 Bitter Orange and Desvenlafaxine 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 Bitter Orange
Top 25%

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

29 days ago today
Medication Desvenlafaxine
Top 25%

#506 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 Bitter Orange

What is Bitter Orange?

Bitter Orange
  • Weight loss
  • Athletic performance and energy
  • Digestive upset
  • Appetite control
  • Aromatherapy for stress (neroli oil)

Bitter orange is a citrus fruit whose extracts contain synephrine, a mild stimulant often added to weight-loss and energy supplements. Evidence that it works for weight loss or performance is limited, and because it can raise heart rate and blood pressure, people with heart problems, high blood pressure, or who are pregnant should avoid it. Talk to your pharmacist or doctor before using it, especially if you take other stimulants.

Read the full Bitter Orange monograph & all interactions
Medication

About Desvenlafaxine

What Is Desvenlafaxine Used For?

Brand names: Pristiq, Khedezla

Desvenlafaxine extended-release tablets — sold under brand names including Pristiq, Desvenlafaxine ER, Desvenlafaxine Succinate, and others — are approved for the treatment of major depressive disorder (MDD) in adults.

This medication is not approved for use in children or adolescents. Its effectiveness was studied in clinical trials of adult outpatients who met standard diagnostic criteria for MDD.

See full Desvenlafaxine drug information
Keep checking

Other Drugs & Bitter Orange

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

10Major
875Moderate
71Minor
1,873No known interaction
Major

10 interactions

Moderate

875 interactions

Showing 60 of 875 moderate interactions — see all 875 on the Bitter Orange page.

Minor

71 interactions

Showing 60 of 71 minor interactions — see all 71 on the Bitter Orange page.

No interaction 1,873 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 Bitter Orange and Desvenlafaxine Together: Common Questions

Can you take Bitter Orange with Desvenlafaxine?
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.
Why are there 2 interactions listed for Bitter Orange and Desvenlafaxine?
Desvenlafaxine belongs to more than one drug category, and Bitter Orange interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Bitter Orange and Desvenlafaxine 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 Desvenlafaxine and Bitter Orange?

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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.