Drug & supplement interaction

Indian Snakeroot + Carbidopa, Levodopa

Carbidopa, Levodopa brand names: Sinemet CR, Sinemet, Rytary, Dhivy.

Major Interaction
Medically reviewed by · Updated September 2026
The bottom line Major

Indian Snakeroot has a major interaction with Carbidopa, Levodopa. Theoretically, taking Indian snakeroot with levodopa may reduce the effectiveness of levodopa.

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

Indian Snakeroot and Carbidopa, Levodopa

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

Major

LEVODOPA

Why this applies to Carbidopa, Levodopa

Carbidopa, Levodopa falls under LEVODOPA — the group Indian Snakeroot interacts with.

Theoretically, taking Indian snakeroot with levodopa may reduce the effectiveness of levodopa.
Extrapyramidal motor symptoms and Parkinson-like symptoms have been reported in clinical trials using Indian snakeroot. Concomitant use of Indian snakeroot with levodopa may reduce the effectiveness of levodopa and increase extrapyramidal motor symptoms.
Severity Major Likelihood Probable Evidence D

Interaction 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..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the concern with this pairing. Your Sinemet (carbidopa/levodopa) works by replacing the dopamine your brain is missing, which eases tremor, stiffness, and slow movement. The reserpine in Indian snakeroot does the opposite. It drains dopamine and other nerve chemicals out of storage, so it can directly work against your Parkinson's medicine.

In real life, that could mean your levodopa stops controlling symptoms as well, and you might notice more shaking, stiffness, or even involuntary muscle movements. This warning is based on how these compounds behave (theoretical pharmacology), not large head-to-head studies, but the logic is sound and the potential effect is serious. Please don't add Indian snakeroot without first talking to your doctor or pharmacist.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  3. Lobay D. Rauwolfia in the Treatment of Hypertension. Integr Med (Encinitas). 2015 Jun;14(3):40-6.
  4. Vakil RJ. A clinical trial of Rauwolfia serpentina in essential hypertension. Br Heart J. 1949 Oct;11(4):350-5. 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

Indian Snakeroot Also Interacts With Other Medications

Indian Snakeroot has 82 major, 760 moderate known drug interactions in our database — the Carbidopa, Levodopa one above is one of them. If you take anything else, check it against the full list below.

Major 82 Moderate 760 No known interaction 1,988 (incl. Carbidopa, Levodopa)
Taking anything else?

Check Another of Your Medications Against Indian Snakeroot

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

Everything else you take

See Every Supplement That Interacts With Carbidopa, Levodopa

This page covers Indian Snakeroot only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Carbidopa, Levodopa page lists 43 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Branched-chain Amino Acids (bcaa) (major), Cowhage (major), Magnesium (major) and Phenylalanine (major).

By severity: 8 major · 24 moderate · 11 minor.

From our pharmacist’s overview on the Carbidopa, Levodopa page

“Carbidopa/levodopa (Sinemet, Rytary) anchors Parkinson's treatment, and because symptom control hinges on how much levodopa actually reaches the brain, the 43 supplements and herbs on this list deserve real respect before you add any of them. Eight carry a major rating, and almost all of the serious entries weaken the drug rather than…”

Reviewed by 2 · Jul 18, 2026

Open the Carbidopa, Levodopa interaction page

One more smart check

Taking Indian Snakeroot as Part of a Dietary Supplement Product? Check It for Interactions

We hold 70 real supplement products containing Indian Snakeroot, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Indian Snakeroot. Your product may carry other ingredients that interact with Carbidopa, Levodopa too, on top of Indian Snakeroot — 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 Indian Snakeroot and Carbidopa, Levodopa 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 Indian Snakeroot
Top half

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

29 days ago today
Medication Carbidopa, Levodopa
Top 5%

#86 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 Indian Snakeroot

What is Indian Snakeroot?

Indian Snakeroot
  • High blood pressure
  • Anxiety and stress
  • Insomnia
  • Agitation
  • Fever (traditional use)

Indian snakeroot is a traditional Ayurvedic plant that contains reserpine, a compound with real blood-pressure-lowering and sedative effects. Because its potent alkaloids can cause serious side effects like depression and very low blood pressure, it should never be used without medical supervision. It is not a safe or simple home remedy, and many countries restrict its use.

Read the full Indian Snakeroot monograph & all interactions
Medication

About Levodopa and Carbidopa

What Is Levodopa and Carbidopa Used For?

Brand names: Sinemet CR, Sinemet, Rytary, Dhivy

Levodopa and carbidopa is used to treat Parkinson's disease, post-encephalitic parkinsonism (parkinsonism that develops after a brain infection), and symptomatic parkinsonism that can follow carbon monoxide or manganese poisoning. These indications are shared across the oral tablet, orally disintegrating tablet, extended-release tablet, and extended-release capsule formulations (including Sinemet, Rytary, Crexont, and generic products).

DUOPA — a carbidopa/levodopa suspension given through a tube directly into the small intestine — is specifically indicated for the treatment of motor fluctuations in patients with advanced Parkinson's disease. This is a product-specific indication and does not apply to the oral forms.

See full Levodopa and Carbidopa drug information
Keep checking

Other Drugs & Indian Snakeroot

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

82Major
760Moderate
0Minor
1,987No known interaction
82 Major 760 Moderate 1,987 No interaction
Major

82 interactions

Showing 60 of 82 major interactions — see all 82 on the Indian Snakeroot page.

Moderate

760 interactions

Showing 60 of 760 moderate interactions — see all 760 on the Indian Snakeroot page.

No interaction 1,987 drugs checked — show the list

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

Showing the 60 most looked-up of 1,987 medications checked with no known interaction — see the full Indian Snakeroot list.

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

Can you take Indian Snakeroot with Carbidopa, Levodopa?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Indian Snakeroot and Carbidopa, Levodopa interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Carbidopa, Levodopa and Indian Snakeroot?

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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.