Drug & supplement interaction

Hydrangea + Lithium Carbonate (prescription drug)

Lithium Carbonate (prescription drug) brand names: Eskalith, Lithium Carbonate.

Moderate Interaction
The bottom line Moderate

Hydrangea has a moderate interaction with Lithium Carbonate (prescription drug). Hydrangea is thought to have diuretic properties.

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

Hydrangea and Lithium Carbonate (prescription drug)

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

Moderate

LITHIUM

Hydrangea is thought to have diuretic properties. Theoretically, due to these potential diuretic effects, hydrangea might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.
Severity Moderate 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 combining hydrangea root and your lithium. Lithium isn't broken down by the liver, instead your kidneys clear it out through your urine. Hydrangea is thought to act like a mild water pill (a diuretic), and anything that changes how your kidneys handle fluid and salt can shift how much lithium stays in your body. The worry is that lithium levels could creep up.

That matters because lithium has a very narrow safe range. Even small increases can tip you toward toxicity, with signs like nausea, hand tremors, unusual drowsiness, confusion, or trouble with balance. I want to be honest though: this is a theoretical concern based on pharmacology, not proven in studies. Still, with a drug this finicky, please check with your doctor or pharmacist before adding hydrangea.

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.

From our Q&A

Questions About Hydrangea or Lithium Carbonate (prescription drug)

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Hydrangea or Lithium Carbonate (prescription drug), 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 Lithium Carbonate (prescription drug)

This page covers Hydrangea only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Lithium Carbonate (prescription drug) page lists 189 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Asarabacca (major), Beer (major) and Gamma-hydroxybutyrate (ghb) (major).

By severity: 12 major · 163 moderate · 14 minor.

From our pharmacist’s overview on the Lithium Carbonate (prescription drug) page

“Lithium carbonate (Eskalith) steadies mood in bipolar disorder, but it works within a narrow blood-level window, meaning a small shift up risks toxicity and a shift down risks relapse. The 189 supplements and herbs listed here therefore call for genuine vigilance.”

Reviewed by 2 · Jul 18, 2026

Open the Lithium Carbonate (prescription drug) interaction page

One more smart check

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

We hold 337 real supplement products containing Hydrangea, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hydrangea. Your product may carry other ingredients that interact with Lithium Carbonate (prescription drug) too, on top of Hydrangea — 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 Hydrangea and Lithium Carbonate (prescription drug) 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 Hydrangea
Top 25%

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

29 days ago today
Medication Lithium Carbonate (prescription drug)
Top half

#1,037 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 Hydrangea

What is Hydrangea?

  • Kidney and bladder stones
  • Urinary tract complaints
  • Enlarged prostate symptoms
  • Mild diuretic (increasing urine)
  • Bladder infections (traditional use)

Hydrangea root has a long history in folk medicine, mainly for urinary and kidney stone complaints, but there is very little modern human research to confirm it works for any condition. Because safety data are limited and large amounts may be harmful, it is best to talk with a pharmacist or doctor before using it.

Read the full Hydrangea monograph & all interactions
Medication

About Lithium

What Is Lithium Used For?

Brand names: Eskalith, Lithium Carbonate

Lithium is used to treat acute manic and mixed episodes in bipolar I disorder and as maintenance therapy to reduce how often and how severely manic episodes return. It is approved for adults and children ages 7 and older.

Lithium Carbonate capsules, tablets, and extended-release tablets, as well as Lithium oral solution, are all indicated for these uses in bipolar I disorder. Maintenance therapy with lithium helps prevent future episodes or makes them less intense when they do occur.

See full Lithium drug information
Keep checking

Other Drugs & Hydrangea

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

0Major
0Moderate
0Minor
2,829No known interaction
No interaction 2,829 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 Hydrangea and Lithium Carbonate (prescription drug) Together: Common Questions

Can you take Hydrangea with Lithium Carbonate (prescription drug)?
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 Hydrangea and Lithium Carbonate (prescription drug) 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 Lithium Carbonate (prescription drug) and Hydrangea?

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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.