The short answer
Review concentrated bitter orange with your prescriber before combining it with nortriptyline. Blood-pressure effects are possible, but a specific combined QT or arrhythmia risk has not been measured.
What this answer covers
Citrus aurantium oral extract, not ordinary food portions, topical oil or every isolated synephrine product.
- Supplement or preparation
- Citrus aurantium
- Medication ingredient
- nortriptyline
Why the medicine matters
Nortriptyline requires careful supervision with sympathomimetic medicines and has cardiovascular warnings. This makes the activity and contents of a concentrated bitter orange product relevant to review.
What one extract study found
A single-dose study in fifteen healthy adults found higher pressure and heart rate than placebo during parts of follow-up. It did not test nortriptyline or establish QT prolongation.
Products and findings differ
NCCIH describes inconsistent cardiovascular findings. Serious reports often involved several ingredients, so a stimulant mixture is not evidence that bitter orange alone caused the event.
Review symptoms and the whole label
Bring the extract strength and every added stimulant to the pharmacist. Fainting, chest pain or a new sustained irregular heartbeat needs prompt medical assessment.
Evidence and practical considerations
Side effects & toxicity
Conditional cardiovascular precaution is reasonable; exact-pair arrhythmia, QT prolongation and event rates remain unproved.
- Exact scope
- Citrus aurantium oral extract, not ordinary food portions, topical oil or every isolated synephrine product. with Exact oral nortriptyline hydrochloride capsules. RxNorm IN 7531/PIN 203130 hydrochloride. A nortriptyline measurement during amitriptyline use represents a metabolite exposure, not directly prescribed nortriptyline.
- Medication form and route
- oral
- Timing or duration
- Source-specific single-dose, repeated-dose and observational exposures distinguished.
What remains uncertain
- Small extract study without nortriptyline; mixed-product reports cannot isolate the herb.
Factors that may matter: preparation and plant part; clinical indication; dose; other medicines; baseline alertness.
Read the supporting source summaries
Source 1: current product label
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: People prescribed oral nortriptyline.
Exact label names tryptophan and St John’s wort in serotonin-syndrome warnings; CYP2D6, cardiovascular and anticholinergic interactions require individual review.
How this applies: RxNorm IN 7531/PIN 203130 hydrochloride. A nortriptyline measurement during amitriptyline use represents a metabolite exposure, not directly prescribed nortriptyline.
No universal supplement interval, event rate or preparation equivalence established. Original label distinguishes warnings from measured pair-specific results.
Source 2: original human study
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: Fifteen healthy adults in a placebo-controlled crossover study.
Systolic pressure, diastolic pressure and heart rate were higher than placebo during parts of the five-hour assessment.
How this applies: Only the named drug, preparation, route and measured endpoints apply.
No nortriptyline co-use or QT endpoint in abstract. Diastolic values can be higher than placebo while still below baseline; extract is not every isolated synephrine product.
Source 3: official botanical guidance
nccih.nih.gov · Source check Sep 10, 2026
Population: Bitter orange product users.
Cardiovascular findings are inconclusive; serious event reports often involved multiple-ingredient products, and content can vary.
How this applies: Preparation-specific caution; ordinary food and concentrated products differ.
Does not establish exact nortriptyline co-use risk or isolate bitter orange as cause of mixed-product events.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Current exact available claims adjudicated using original captures and explicit identity and comparator limits. | |
| Research summary published |
Article revision: 0306a5f62b5b3304
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.