Drug & supplement interaction

Coffee + Chlorthalidone

Chlorthalidone brand names: Hygroton, Thalitone.

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

Coffee has a moderate interaction with Chlorthalidone. Theoretically, concomitant use might increase the risk of hypokalemia.

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

Coffee and Chlorthalidone

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

Moderate

DIURETIC DRUGS

Why this applies to Chlorthalidone

Chlorthalidone falls under DIURETIC DRUGS — the group Coffee interacts with.

Theoretically, concomitant use might increase the risk of hypokalemia.
Coffee contains caffeine. Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.
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: chlorthalidone is a water pill that makes your kidneys flush out extra salt and water, but it can also pull potassium down along the way. Coffee's caffeine may nudge potassium a little lower too, since it can push potassium into your cells. So the worry here is that combining the two might add up and leave your potassium on the low side.

I'll be honest with you, this one is mostly theoretical based on how caffeine behaves, not strong real-world proof. A normal cup or two with your morning dose is unlikely to cause trouble. If you're drinking large amounts daily and ever notice muscle cramps, weakness, or an odd heartbeat, mention it to your doctor or pharmacist, since they can simply check your potassium.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Norager, C. B., Jensen, M. B., Weimann, A., and Madsen, M. R. Metabolic effects of caffeine ingestion and physical work in 75-year old citizens. A randomized, double-blind, placebo-controlled, cross-over study. Clin Endocrinol (Oxf) 2006;65(2):223-228. PubMed
  2. Simmonds, M. J., Minahan, C. L., and Sabapathy, S. Caffeine improves supramaximal cycling but not the rate of anaerobic energy release. Eur.J Appl Physiol 2010;109(2):287-295. PubMed
  3. Rigato, I., Blarasin, L., and Kette, F. Severe hypokalemia in 2 young bicycle riders due to massive caffeine intake. Clin J Sport Med. 2010;20(2):128-130. PubMed
  4. Ernest, D., Chia, M., and Corallo, C. E. Profound hypokalaemia due to Nurofen Plus and Red Bull misuse. Crit Care Resusc. 2010;12(2):109-110. DOI
  5. Clausen, T. Hormonal and pharmacological modification of plasma potassium homeostasis. Fundam.Clin Pharmacol 2010;24(5):595-605. 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

Coffee Also Interacts With Other Medications

Coffee has 8 major, 466 moderate, 116 minor known drug interactions in our database — the Chlorthalidone one above is one of them. If you take anything else, check it against the full list below.

Major 8 Moderate 466 Minor 116 No known interaction 2,240 (incl. Chlorthalidone)
Taking anything else?

Check Another of Your Medications Against Coffee

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

From our Q&A

Questions About Coffee or Chlorthalidone

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

This page covers Coffee only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Chlorthalidone page lists 222 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), Dolomite (major) and Lithium (major).

By severity: 8 major · 190 moderate · 24 minor.

From our pharmacist’s overview on the Chlorthalidone page

“Chlorthalidone (Hygroton, Thalitone) lowers blood pressure by helping the kidneys shed salt and water, and that mechanism makes its supplement interactions worth genuine care. Most of the 222 ingredients on file either add to its blood-pressure-lowering effect or act as diuretics themselves, so pressure or potassium can fall further th…”

Reviewed by 2 · Jul 18, 2026

Open the Chlorthalidone interaction page

One more smart check

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

We hold 716 real supplement products containing Coffee, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Coffee. Your product may carry other ingredients that interact with Chlorthalidone too, on top of Coffee — 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 Coffee and Chlorthalidone 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 Coffee
Top 5%

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

29 days ago today
Medication Chlorthalidone
Steady interest

#1,584 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 Coffee

What is Coffee?

  • Alertness and reducing fatigue
  • Mental focus and concentration
  • Athletic performance
  • Headache relief
  • Weight management

Coffee is a widely consumed beverage made from roasted coffee beans, valued mainly for its caffeine, which boosts alertness and energy. For most healthy adults, moderate coffee intake is generally safe and may have some health benefits, but too much can cause jitteriness, poor sleep, and a faster heartbeat. People who are pregnant, breastfeeding, or sensitive to caffeine should limit their intake and check with a doctor or pharmacist.

Read the full Coffee monograph & all interactions
Medication

About Chlorthalidone

What Is Chlorthalidone Used For?

Brand names: Hygroton, Thalitone

Chlorthalidone is used to treat high blood pressure (hypertension) in adults. Lowering blood pressure reduces the risk of serious cardiovascular events, especially strokes and heart attacks. It can be used alone or combined with other blood pressure medicines.

Chlorthalidone is also used as an add-on treatment for edema (fluid buildup) caused by heart failure, liver cirrhosis, and kidney conditions including nephrotic syndrome, acute glomerulonephritis, and chronic renal failure. Thalitone is additionally indicated for edema associated with heart failure, liver cirrhosis, and renal disease including nephrotic syndrome.

See full Chlorthalidone drug information
Keep checking

Other Drugs & Coffee

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

8Major
466Moderate
116Minor
2,239No known interaction
8 Major 466 Moderate 116 Minor 2,239 No interaction
Major

8 interactions

Moderate

466 interactions

Showing 60 of 466 moderate interactions — see all 466 on the Coffee page.

Minor

116 interactions

Showing 60 of 116 minor interactions — see all 116 on the Coffee page.

No interaction 2,239 drugs checked — show the list

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

Showing the 60 most looked-up of 2,239 medications checked with no known interaction — see the full Coffee list.

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

Can you take Coffee with Chlorthalidone?
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 Coffee and Chlorthalidone 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 Chlorthalidone and Coffee?

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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.