The short answer
Review melatonin before adding it to nortriptyline. Severe sedation has been reported during co-use, although citalopram and oxycodone were also present and prevent isolating this pair.
What this answer covers
Oral melatonin product added to nortriptyline with other centrally active medicines.
- Supplement or preparation
- Melatonin
- Medication ingredient
- nortriptyline
What the case reported
A young adult developed severe sedation after adding melatonin while taking nortriptyline, citalopram and oxycodone. Sedation improved when melatonin was removed and worsened again with re-use.
Why the other medicines matter
Complete improvement also required stopping oxycodone. The report cannot assign the effect to nortriptyline plus melatonin alone.
The mechanism remains uncertain
No drug levels were measured in the patient. Laboratory findings differed among melatonin products and cannot establish a clinical nortriptyline metabolism effect or a safe timing gap.
Watch for impaired alertness
Nortriptyline can affect alertness and coordination. Avoid driving if affected and contact the prescriber if added sleepiness, confusion or unsteadiness appears after a new product. Severe confusion, fainting or inability to wake needs urgent assessment.
Evidence and practical considerations
Side effects & toxicity
Conditional alertness precaution supported by a direct but strongly confounded coexposure case.
- Exact scope
- Oral melatonin product added to nortriptyline with other centrally active medicines. 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
- One patient, no blood levels and multiple medicines; no exact-pair incidence, established CYP mechanism or universal dose threshold.
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 case report with laboratory follow-up
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: One 19-year-old taking nortriptyline, citalopram and oxycodone.
Severe sedation improved after melatonin withdrawal and recurred with rechallenge; full clearance also required oxycodone discontinuation.
How this applies: Only the named drug, preparation, route and measured endpoints apply.
Multiple medicines and coffee use confounded attribution; no plasma levels. Laboratory enzyme findings do not establish a nortriptyline-specific clinical PK mechanism.
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: 71948c8a15fe43fa
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.