Drug & supplement interaction

Cesium + Levothyroxine, Liothyronine

Levothyroxine, Liothyronine brand name: Armour Thyroid.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 13, 2026
The bottom line No known interaction

We found no known interaction between Cesium and Levothyroxine, Liothyronine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Cesium and Levothyroxine, Liothyronine

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Levothyroxine, Liothyronine and Cesium in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Cesium safety at a glance

Cesium overall Avoid Cesium chloride can cause life-threatening heart rhythm problems and has no proven benefit.
Pregnancy Avoid Not safe; avoid during pregnancy due to serious toxicity risks.
Breastfeeding Avoid Not safe; avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Levothyroxine, Liothyronine and Cesium? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Levothyroxine, Liothyronine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Levothyroxine, Liothyronine is filed under 3 classifications — including thyroid hormone, oral drugs. Cesium has documented interactions with 3 drug classes — the most serious being qt interval-prolonging drugs (major), corticosteroids (moderate) and diuretic drugs (moderate) — and none of Levothyroxine, Liothyronine’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Cesium Does Interact With Other Medications

Cesium has 161 major, 94 moderate known drug interactions in our database — Levothyroxine, Liothyronine isn’t one of them. If you take anything else, check it against the full list below.

Major 161 Moderate 94 No known interaction 2,575 (incl. Levothyroxine, Liothyronine)
Taking anything else?

Check Another of Your Medications Against Cesium

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

What to actually watch for

What Cesium Itself Has Been Linked To

This is not an interaction — nothing below involves Levothyroxine, Liothyronine. It is the side-effect record for Cesium on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Cesium, this list is the first place to look. 2 entries are worth acting on rather than waiting out — marked below.

  • Low potassium / An irregular heartbeat Worth acting on Additional detail

    “Orally and by injection, cesium has been associated with hypokalemia. In multiple case reports, patients presented with hypokalemia and arrhythmia that resolved after discontinuation of cesium supplementation. It is not clear whether these reports of hypokalemia were due to a direct effect of cesium on potassium channels.”

    Cesium · Natural Medicines adverse-effect record, reported in arrhythmia.

    3 sources cited
    1. 12178. Lyon AW, Mayhew WJ. Cesium toxicity: A case of self-treatment by alternate therapy gone awry. Ther Drug Monit 2003;25:114-6. PubMed
    2. 15262. Vyas H, Johnson K, Houlihan R, et al. Acquired long QT syndrome secondary to cesium chloride supplement. J Altern Complement Med 2006;12:1011-4. PubMed
    3. 16690. Pinter A, Dorian P, Newman D. Cesium-induced torsades de pointes. N Engl J Med 2002;346:383-4. PubMed
  • Fainting / Seizures Worth acting on Additional detail

    “Orally and by injection, cesium chloride has been associated with arrhythmias such as ventricular tachycardia, QT prolongation, cardiac arrest, seizures, and death. There are at least 23 reports of cardiotoxicity or death in patients taking cesium supplements.

    In one case report, a healthy 39-year-old female taking an unknown amount of cesium chloride as part of a "detoxification" program developed three episodes of…”

    Cesium · Natural Medicines adverse-effect record, reported in arrhythmia.

    6 sources cited
    1. 101651. Public Health Alert Concerning Dietary Supplements Containing Cesium Salts. FDA Dietary Supplement Products & Ingredients. February 5, 2020. Available at: https://www.fda.gov/food/dietary-supplement-products-ingredients/public-health-alert-concerning-diet
    2. 15262. Vyas H, Johnson K, Houlihan R, et al. Acquired long QT syndrome secondary to cesium chloride supplement. J Altern Complement Med 2006;12:1011-4. PubMed
    3. 12178. Lyon AW, Mayhew WJ. Cesium toxicity: A case of self-treatment by alternate therapy gone awry. Ther Drug Monit 2003;25:114-6. PubMed
    4. 16689. Cesium chloride and ventricular arrhythmias. Canadian Adverse Reaction Newsletter 2008;18:3-4.
    5. 16690. Pinter A, Dorian P, Newman D. Cesium-induced torsades de pointes. N Engl J Med 2002;346:383-4. PubMed
    6. 16691. O'Brien CE, Harik N, James LP, et al. Cesium-induced QT-interval prolongation in an adolescent. Pharmacotherapy 2008;28:1059-65. PubMed
  • A fast or pounding heartbeat Additional detail

    Recorded for Cesium in the same Natural Medicines adverse-effect record shown under Fainting / Seizures above.

  • Numbness or tingling Additional detail

    Recorded for Cesium in the same Natural Medicines adverse-effect record shown under Low potassium / An irregular heartbeat above.

  • Reduced appetite Additional detail

    “Orally, cesium can cause nausea, diarrhea, and anorexia.”

    Cesium · Natural Medicines adverse-effect record, reported in anorexia.

    1 source cited
    1. 7671. Neulieb R. Effect of oral intake of cesium chloride: a single case report. Pharmacol Biochem Behav 1984;21:15-6.
  • Diarrhea / Nausea Additional detail

    Recorded for Cesium in the same Natural Medicines adverse-effect record shown under Low potassium / An irregular heartbeat above.

Everything above comes from the Natural Medicines adverse-effect record for Cesium — expand a row for the licensed statement it rests on. We haven’t matched Levothyroxine, Liothyronine to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Levothyroxine, Liothyronine.

Everything else you take

See Every Supplement That Interacts With Levothyroxine, Liothyronine

This page covers Cesium only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Levothyroxine, Liothyronine page lists 50 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Tiratricol (major), Acetyl-l-carnitine (moderate), Alpha-lipoic Acid (moderate) and Ascophyllum Nodosum (moderate).

By severity: 2 major · 39 moderate · 9 minor.

From our pharmacist’s overview on the Levothyroxine, Liothyronine page

“For anyone taking levothyroxine or liothyronine (Armour Thyroid), this list earns real caution, not just a passing glance. Most of these 50 ingredients pull in one of two directions.”

Reviewed by 2 · Jul 18, 2026

Open the Levothyroxine, Liothyronine interaction page

One more smart check

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

We hold 51 real supplement products containing Cesium, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cesium. Even though Cesium itself has no known interaction with Levothyroxine, Liothyronine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Cesium and Levothyroxine, Liothyronine 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 Cesium
Steady interest

#1,012 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Levothyroxine, Liothyronine
Top 5%

#61 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Cesium reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Cesium and Levothyroxine, Liothyronine records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Cesium

What is Cesium?

  • Marketed as an alternative cancer treatment ('high pH therapy')
  • Claimed to alter tumor pH
  • General 'alkaline' health claims

Cesium chloride is a mineral salt sold as an alternative cancer therapy ('high pH therapy'), but there is no reliable scientific evidence that it treats cancer or any other disease. It can cause dangerous heart rhythm problems and even death, so it should not be used. Talk to your doctor or pharmacist before taking any supplement, and never use cesium in place of proven medical care.

Mineral element (cesium chloride salt) · Capsules, powders, liquid solutions (often as cesium chloride)

An interaction check asks whether these two react with each other — it does not ask whether Cesium is a good idea for someone in your situation. Here is what our Cesium record says about it on its own.

Cesium: dosing

There is no safe or established dose for cesium chloride, and it is not approved as a medicine. Because it can cause life-threatening harm, no dosing recommendation can be given.We strongly advise against taking cesium chloride.

From our Cesium monograph — the full record covers uses, side effects and every documented interaction.

Read the full Cesium monograph & all interactions
Medication

About Levothyroxine, Liothyronine

Most-Reported Side Effects for Levothyroxine, Liothyronine

From FAERS, the FDA’s public side-effect reporting system (15 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Fatigue 4 reports
Asthenia 3 reports
Dizziness 3 reports
Arthralgia 2 reports
Disorientation 2 reports
Keep checking

Other Drugs & Cesium

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

161Major
94Moderate
0Minor
2,574No known interaction
161 Major 94 Moderate 2,574 No interaction
Major

161 interactions

Showing 60 of 161 major interactions — see all 161 on the Cesium page.

Moderate

94 interactions

Showing 60 of 94 moderate interactions — see all 94 on the Cesium page.

No interaction 2,574 drugs checked — show the list

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

Showing the 60 most looked-up of 2,574 medications checked with no known interaction — see the full Cesium list.

See the full Cesium interactions page
See every supplement checked against Levothyroxine, Liothyronine, ranked by severity
Evidence & sources

Cesium References

The 9 references that drive our Cesium monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Sartori HE. Nutrients and cancer: an introduction to cesium therapy. Pharmacol Biochem Behav 1984;21:7-10. PubMed
  2. Neulieb R. Effect of oral intake of cesium chloride: a single case report. Pharmacol Biochem Behav 1984;21:15-6.
  3. Lyon AW, Mayhew WJ. Cesium toxicity: A case of self-treatment by alternate therapy gone awry. Ther Drug Monit 2003;25:114-6. PubMed
  4. Vyas H, Johnson K, Houlihan R, et al. Acquired long QT syndrome secondary to cesium chloride supplement. J Altern Complement Med 2006;12:1011-4. PubMed
  5. Cesium chloride and ventricular arrhythmias. Canadian Adverse Reaction Newsletter 2008;18:3-4.
  6. Pinter A, Dorian P, Newman D. Cesium-induced torsades de pointes. N Engl J Med 2002;346:383-4. PubMed
  7. O'Brien CE, Harik N, James LP, et al. Cesium-induced QT-interval prolongation in an adolescent. Pharmacotherapy 2008;28:1059-65. PubMed
  8. FDA alerts health care professionals of significant safety risks associated with cesium chloride. FDA: Human Drug Compounding. July 23,2018. Available at: https://www.fda.gov/drugs/human-drug-compounding/fda-alerts-health-care-professionals-significant-sa
  9. Public Health Alert Concerning Dietary Supplements Containing Cesium Salts. FDA Dietary Supplement Products & Ingredients. February 5, 2020. Available at: https://www.fda.gov/food/dietary-supplement-products-ingredients/public-health-alert-concerning-diet

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Cesium and Levothyroxine, Liothyronine Together: Common Questions

Is it safe to take Cesium with Levothyroxine, Liothyronine?
We do not list a known interaction between Cesium and Levothyroxine, Liothyronine. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Cesium and Levothyroxine, Liothyronine combination checked?
Interactions in our licensed database are recorded against drug classes. Levothyroxine, Liothyronine is filed under 3 classifications, and Cesium has documented interactions with 3 drug classes — none of Levothyroxine, Liothyronine's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Cesium interact with any other medications?
Yes. Cesium has 255 documented drug interactions in our database — Levothyroxine, Liothyronine is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Levothyroxine, Liothyronine interact with any supplements?
Yes. Levothyroxine, Liothyronine has documented interactions with 50 supplements in our database — Cesium is not one of them. The Levothyroxine, Liothyronine interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Cesium monograph Uses, safety profile, and every drug interaction in one place Levothyroxine, Liothyronine supplement interactions Every supplement checked against Levothyroxine, Liothyronine, 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 References The 9 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Levothyroxine, Liothyronine and Cesium?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.