Drug & supplement interaction

Syrian Rue + Dexmethylphenidate

Dexmethylphenidate brand name: Focalin.

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

Syrian Rue has a moderate interaction with Dexmethylphenidate. Theoretically, Syrian rue might increase the risk of serotonergic adverse effects, including serotonin syndrome, when taken with serotonergic drugs.

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

Syrian Rue and Dexmethylphenidate

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

Moderate

SEROTONERGIC DRUGS

Why this applies to Dexmethylphenidate

Dexmethylphenidate falls under SEROTONERGIC DRUGS — the group Syrian Rue interacts with.

Theoretically, Syrian rue might increase the risk of serotonergic adverse effects, including serotonin syndrome, when taken with serotonergic drugs.
Syrian rue contains harmaline and harmine, which have demonstrated strong, reversible inhibition of monoamine oxidase (MAO) A and weak inhibition of MAO B in animal and in vitro research. This may increase the risk for adverse effects with serotonergic drugs.
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 Syrian Rue and Focalin (dexmethylphenidate). Syrian Rue's harmala alkaloids act like a natural MAO inhibitor, meaning they slow down an enzyme that normally clears out brain chemicals like dopamine and norepinephrine. Focalin is a stimulant that already raises those same chemicals. Stacking the two could let them climb higher than intended.

Realistically, that might show up as a racing or pounding heart, a spike in blood pressure, jitteriness, agitation, or trouble sleeping, and in rare cases a dangerous reaction called serotonin syndrome (sweating, confusion, shaking, fever). I'll be honest: this warning is theoretical, based on lab and animal studies, not solid human data. Still, combining stimulants with MAO inhibitors is a well-known caution. Please check with your pharmacist or doctor before mixing these.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Kawanishi, K., Hashimoto, Y., Fujiwara, M., Kataoka, Y., and Ueki, S. Pharmacological characteristics of abnormal behavior induced by harmine with special reference to tremor in mice. J Pharmacobiodyn 1981;4(7):520-527. PubMed
  2. Herraiz, T., Gonzalez, D., Ancin-Azpilicueta, C., Aran, V. J., and Guillen, H. beta-Carboline alkaloids in Peganum harmala and inhibition of human monoamine oxidase (MAO). Food Chem Toxicol 2010;48(3):839-845. PubMed
  3. Fuller, R. W., Wong, C. J., and Hemrick-Luecke, S. K. MD 240928 and harmaline: opposite selectivity in antagonism of the inactivation of types A and B monoamine oxidase by pargyline in mice. Life Sci 1986;38(5):409-412. PubMed
  4. Abdel-Fattah, A. F., Matsumoto, K., Murakami, Y., Adel-Khalek, Gammaz H., Mohamed, M. F., and Watanabe, H. Central serotonin level-dependent changes in body temperature following administration of tryptophan to pargyline- and harmaline-pretreated rats. Ge PubMed
  5. Bergstrom, M., Westerberg, G., and Langstrom, B. 11C-harmine as a tracer for monoamine oxidase A (MAO-A): in vitro and in vivo studies. Nucl Med Biol 1997;24(4):287-293. PubMed
  6. Gerardy, J. Effect of moclobemide on rat brain monoamine oxidase A and B: comparison with harmaline and clorgyline. Prog Neuropsychopharmacol Biol Psychiatry 1994;18(4):793-802.
  7. Sacher, J., Houle, S., Parkes, J., Rusjan, P., Sagrati, S., Wilson, A. A., and Meyer, J. H. Monoamine oxidase A inhibitor occupancy during treatment of major depressive episodes with moclobemide or St. John's wort: an [11C]-harmine PET study. J Psychiatry

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

Syrian Rue Also Interacts With Other Medications

Syrian Rue has 1,123 moderate known drug interactions in our database — the Dexmethylphenidate one above is one of them. If you take anything else, check it against the full list below.

Moderate 1,123 No known interaction 1,707 (incl. Dexmethylphenidate)
Taking anything else?

Check Another of Your Medications Against Syrian Rue

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

From our Q&A

Questions About Syrian Rue or Dexmethylphenidate

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Syrian Rue or Dexmethylphenidate, 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 Dexmethylphenidate

This page covers Syrian Rue only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dexmethylphenidate page lists 85 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Lithium (major), Peyote (major) and Rauvolfia Vomitoria (major).

By severity: 6 major · 64 moderate · 15 minor.

From our pharmacist’s overview on the Dexmethylphenidate page

“Dexmethylphenidate (Focalin) is itself a prescription stimulant for ADHD, which is exactly why this list deserves real care rather than a quick skim. More than half of the 85 ingredients on file stimulate the nervous system too, so combining them can compound the racing heart, raised blood pressure, and sleeplessness the drug can alrea…”

Reviewed by 2 · Jul 18, 2026

Open the Dexmethylphenidate interaction page

How much people look this up

Where Syrian Rue and Dexmethylphenidate 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 Syrian Rue
Steady interest

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

29 days ago today
Medication Dexmethylphenidate
Top 25%

#415 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 Syrian Rue

What is Syrian Rue?

  • Traditional remedy for digestive complaints
  • Used as a sedative or for mood
  • Antimicrobial and antiparasitic folk use
  • Used as a dye and incense
  • Recreational psychoactive use

Syrian Rue (Peganum harmala) is a traditional plant whose seeds contain potent compounds called harmala alkaloids, including MAO-inhibiting harmine and harmaline. There is little reliable human evidence that it safely treats any condition, and it carries real risks of toxicity, so it is not recommended for self-treatment. Talk to a pharmacist or doctor before considering it.

Read the full Syrian Rue monograph & all interactions
Medication

About Dexmethylphenidate

What Is Dexmethylphenidate Used For?

Brand name: Focalin

Dexmethylphenidate treats attention deficit hyperactivity disorder (ADHD). Every product in this group is approved for that use: dexmethylphenidate tablets, Focalin tablets, dexmethylphenidate extended-release capsules and Focalin XR extended-release capsules.

The extended-release capsules (dexmethylphenidate and Focalin XR) are not recommended for children younger than 6 years. In that age group, blood levels were higher and side effects such as weight loss were more common.

See full Dexmethylphenidate drug information
Keep checking

Other Drugs & Syrian Rue

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

0Major
1,123Moderate
0Minor
1,706No known interaction
1,123 Moderate 1,706 No interaction
Moderate

1,123 interactions

Showing 60 of 1,123 moderate interactions — see all 1,123 on the Syrian Rue page.

No interaction 1,706 drugs checked — show the list

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

Showing the 60 most looked-up of 1,706 medications checked with no known interaction — see the full Syrian Rue list.

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

Can you take Syrian Rue with Dexmethylphenidate?
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 Syrian Rue and Dexmethylphenidate 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 Dexmethylphenidate and Syrian Rue?

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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.