Drug & supplement interaction

Tinospora Cordifolia + Dextromethorphan HBr, Phenylephrine HCl

Dextromethorphan HBr, Phenylephrine HCl brand name: Vicks Formula 44D Cough & Head Congestion Relief.

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

Tinospora Cordifolia has a moderate interaction with Dextromethorphan HBr, Phenylephrine HCl. Theoretically, Tinospora cordifolia might increase levels of drugs metabolized by CYP2D6.

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

Tinospora Cordifolia and Dextromethorphan HBr, Phenylephrine HCl

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

Moderate

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

Why this applies to Dextromethorphan HBr, Phenylephrine HCl

Dextromethorphan HBr, Phenylephrine HCl falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES — the group Tinospora Cordifolia interacts with.

Theoretically, Tinospora cordifolia might increase levels of drugs metabolized by CYP2D6.
In vitro research shows that Tinospora cordifolia extract inhibits CYP2D6 at high concentrations. However, this interaction has not been reported in humans.
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 with Giloy and this cough-and-congestion combo. The dextromethorphan part is cleared mostly by a liver enzyme called CYP2D6. In lab dish studies, Tinospora cordifolia (Giloy) has slowed that enzyme down, which could let dextromethorphan build up a bit. If that happened, you might feel more of its side effects, like drowsiness, dizziness, or a foggy, lightheaded feeling.

I want to keep this in perspective though. This signal comes only from test-tube research at high concentrations, and it has not actually been reported in people. So it's more theoretical than proven. Since Giloy has also been linked to liver injury, I'd run it by your pharmacist or doctor before combining them, especially if you take it daily.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Sahu R, Ahmed T, Sangana R, Punde R, Subudhi BB. Effect of Tinospora cordifolia aqua-alcoholic extract on pharmacokinetic of glibenclamide in rat: an herb-drug interaction study. J Pharm Biomed Anal. 2018;151:310-6. doi: 10.1016/j.jpba.2018.01.010. 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

Tinospora Cordifolia Also Interacts With Other Medications

Tinospora Cordifolia has 613 moderate known drug interactions in our database — the Dextromethorphan HBr, Phenylephrine HCl one above is one of them. If you take anything else, check it against the full list below.

Moderate 613 No known interaction 2,217 (incl. Dextromethorphan HBr, Phenylephrine HCl)
Taking anything else?

Check Another of Your Medications Against Tinospora Cordifolia

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

Everything else you take

See Every Supplement That Interacts With Dextromethorphan HBr, Phenylephrine HCl

This page covers Tinospora Cordifolia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dextromethorphan HBr, Phenylephrine HCl page lists 197 supplements it has a documented interaction with, worst first, each one explained.

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

By severity: 8 major · 148 moderate · 41 minor.

From our pharmacist’s overview on the Dextromethorphan HBr, Phenylephrine HCl page

“The supplement interactions with Dextromethorphan HBr and Phenylephrine HCl (Vicks Formula 44D) deserve real respect, and the small cluster of major-rated ones should be understood before you reach for the bottle. Phenylephrine is a stimulant-type decongestant, so anything with caffeine (coffee, tea, cola nut) or ephedrine-like herbs s…”

Reviewed by 2 · Jul 18, 2026

Open the Dextromethorphan HBr, Phenylephrine HCl interaction page

One more smart check

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

We hold 393 real supplement products containing Tinospora Cordifolia, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Tinospora Cordifolia. Your product may carry other ingredients that interact with Dextromethorphan HBr, Phenylephrine HCl too, on top of Tinospora Cordifolia — 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 Tinospora Cordifolia and Dextromethorphan HBr, Phenylephrine HCl 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 Tinospora Cordifolia
Top 25%

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

29 days ago today
Medication Dextromethorphan HBr, Phenylephrine HCl
Top half

#1,087 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 Tinospora Cordifolia

What is Tinospora Cordifolia?

  • Immune support
  • Fever
  • Blood sugar support
  • General wellness and 'rejuvenation'
  • Allergic rhinitis
  • Inflammation

Tinospora cordifolia, known as Guduchi or Giloy in Ayurvedic medicine, is a climbing plant traditionally used to support immunity and treat fevers. Early laboratory and small human studies suggest possible immune and blood sugar effects, but high-quality evidence is limited, and there have been reports of liver injury. Talk with your pharmacist or doctor before using it.

Read the full Tinospora Cordifolia monograph & all interactions
Keep checking

Other Drugs & Tinospora Cordifolia

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

0Major
613Moderate
0Minor
2,216No known interaction
613 Moderate 2,216 No interaction
Moderate

613 interactions

Showing 60 of 613 moderate interactions — see all 613 on the Tinospora Cordifolia page.

No interaction 2,216 drugs checked — show the list

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

Showing the 60 most looked-up of 2,216 medications checked with no known interaction — see the full Tinospora Cordifolia list.

See the full Tinospora Cordifolia interactions page
See every supplement checked against Dextromethorphan HBr, Phenylephrine HCl, 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
Tinospora Cordifolia monograph › Uses, safety, and every drug interaction in one place Dextromethorphan HBr, Phenylephrine HCl supplement interactions › Every supplement checked against Dextromethorphan HBr, Phenylephrine HCl, ranked by severity 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 Tinospora Cordifolia and Dextromethorphan HBr, Phenylephrine HCl Together: Common Questions

Can you take Tinospora Cordifolia with Dextromethorphan HBr, Phenylephrine HCl?
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 Tinospora Cordifolia and Dextromethorphan HBr, Phenylephrine HCl 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

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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.