Drug & supplement interaction

Cilantro + Polythiazide

Polythiazide brand name: Renese.

Moderate Interaction
The bottom line Moderate

Cilantro has a moderate interaction with Polythiazide. Evidence from in vitro research suggests that coriandrin, a constituent of cilantro, has photosensitizing effects.

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

Cilantro and Polythiazide

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

Moderate

PHOTOSENSITIZING DRUGS

Why this applies to Polythiazide

Polythiazide falls under PHOTOSENSITIZING DRUGS — the group Cilantro interacts with.

Evidence from in vitro research suggests that coriandrin, a constituent of cilantro, has photosensitizing effects. Theoretically, concomitant use with photosensitizing drugs might increase photosensitivity. Some drugs that cause photosensitivity include amitriptyline (Elavil), quinolones (Ciprofloxacin, others), sulfa drugs (Septra, Bactrim, others), and tetracycline.
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 connection worth knowing about. Polythiazide (Renese) is a thiazide-type water pill, and like other thiazides it can make your skin more sensitive to the sun, so you may sunburn faster than usual. Cilantro contains a compound called coriandrin that, at least in lab studies, may also boost sun sensitivity. Put the two together and the concern is simply additive: you could be a little more prone to burning or a sun rash.

I want to keep this in perspective. This is a theoretical interaction based on test-tube research, not real patient reports, and the everyday cilantro you sprinkle on tacos is very unlikely to matter. Concentrated cilantro supplements or essential oil would be the bigger question. Either way, sensible sun protection covers you. Run any cilantro supplement past your pharmacist or doctor first.

References
  1. Ashwood-Smith, M. J., Warrington, P. J., Jenkins, M., Ceska, O., and Romaniuk, P. J. Photobiological properties of a novel, naturally occurring furoisocoumarin, coriandrin. Photochem.Photobiol. 1989;50(6):745-751. 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

Cilantro Also Interacts With Other Medications

Cilantro has 433 moderate known drug interactions in our database — the Polythiazide one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Cilantro

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

Everything else you take

See Every Supplement That Interacts With Polythiazide

This page covers Cilantro only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Polythiazide page lists 227 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Asarabacca (major) and Dolomite (major).

By severity: 10 major · 192 moderate · 25 minor.

From our pharmacist’s overview on the Polythiazide page

“Polythiazide (Renese) is a thiazide diuretic for high blood pressure, and this is a list I would treat with real care. Most entries either add to its blood-pressure-lowering and fluid-losing effects or deepen the potassium loss it already causes, which can leave someone dizzy or set the stage for heart rhythm trouble.”

Reviewed by 2 · Jul 18, 2026

Open the Polythiazide interaction page

How much people look this up

Where Cilantro and Polythiazide 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 Cilantro
Steady interest

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

29 days ago today
Medication Polythiazide
Steady interest

#1,891 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 Cilantro

What is Cilantro?

  • Digestive upset and bloating
  • Antimicrobial support
  • Antioxidant support
  • Heavy metal 'detox' (chelation) claims
  • Culinary flavoring

Cilantro is the leafy part of the Coriandrum sativum plant and is widely eaten as a food, where it is considered safe for most people. While it has antioxidant and antimicrobial properties in lab studies, strong human evidence for any specific health benefit is lacking, and popular 'detox' claims are not well supported. Talk with your pharmacist or doctor before using concentrated cilantro supplements or essential oil.

Read the full Cilantro monograph & all interactions
Keep checking

Other Drugs & Cilantro

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

0Major
433Moderate
0Minor
2,396No known interaction
Moderate

433 interactions

Showing 60 of 433 moderate interactions — see all 433 on the Cilantro page.

No interaction 2,396 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Cilantro and Polythiazide Together: Common Questions

Can you take Cilantro with Polythiazide?
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 Cilantro and Polythiazide 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.