+ -Text Size

Cesium Chloride

Other common name(s): high pH therapy

Scientific/medical name(s): CsCl


Cesium chloride is the salt form of the element cesium. Cesium is a rare, naturally-occurring element of alkali metal with a chemical structure similar to lithium, sodium, and potassium. Cesium can be absorbed by all the body’s cells, probably because its chemical structure is so much like potassium. This is not the same as radioactive cesium, which is used in some types of radiation therapy.


Cesium chloride as an alternative therapy should not be confused with radioactive cesium (cesium-137), which is used in mainstream medicine for certain types of radiation therapy in cancer patients.

Available scientific evidence does not support claims that non-radioactive cesium chloride supplements have any effect on tumors. A few people have had life-threatening problems with heart rhythm, seizures, loss of consciousness, and electrolyte (blood chemistry) imbalances after taking cesium chloride.

How is it promoted for use?

Proponents claim the pH level inside of tumor cells is usually very low, or acidic, compared to normal cells, and that cesium chloride supplements raise the pH level of tumor cells to a normal level, which slows the cancer's growth. Since proponents claim cesium chloride works by raising the pH of the tumor cells, its use in therapy has been called "high pH therapy."

What does it involve?

Cesium chloride supplements can be bought in pill or liquid form. Proponents suggest a dosage of 1 to 6 grams per day, sometimes mixed in juice with other vitamins and minerals. Many cesium supporters now recommend taking potassium supplements along with the cesium to try and reduce the risk of abnormal heart rhythms and other complications. Some practitioners give cesium chloride intravenously (in the vein or through an IV).

What is the history behind it?

Interest in cesium therapy began when scientists observed that certain regions of the world with low rates of certain types of cancer had a high concentration of alkali metals in the soil. As early as the 1920s, some researchers suggested cesium might work as an antitumor agent. However, further research starting in the 1930s suggested cesium had no effect on cancer cell growth. The use of cesium chloride for high pH therapy was first made public in the 1980s.

What is the evidence?

Available scientific evidence does not support the claim that the pH inside cancer cells in the body is any different than that of normal cells, or that the pH inside the body can be changed in any significant way. Thus, the underlying principle behind high pH therapy remains unproven. Although it was observed that certain regions with low rates of cancer had a high concentration of alkali metals in the soil, it has never been shown that this caused the lower cancer rates. Differences in many other risk factors or protective factors are likely to be involved. It has not been shown that cesium can prevent or treat cancer.

Studies conducted in several experimental tumor models in the 1980s found that the use of cesium or cesium chloride led to decreased tumor growth and fewer deaths in certain mice with cancerous tumors, such as those with sarcoma or breast cancer. In animal studies, giving cesium over the long term caused serious blood and neuromuscular side effects and even death.

Animal and laboratory studies may show a substance has helpful effects, but further studies are necessary to learn whether the results apply to humans. So far, there is no reliable clinical evidence available to support claims from proponents of this treatment.

Are there any possible problems or complications?

This product is sold as a dietary supplement in the United States. Unlike companies that produce drugs (which must be tested before being sold), the companies that make supplements are not required to prove to the Food and Drug Administration that their supplements are safe or effective, as long as they don't claim the supplements can prevent, treat, or cure any specific disease.
Some such products may not contain the amount of the herb or substance that is on the label, and some may include other substances (contaminants). Actual amounts per dose may vary between brands or even between different batches of the same brand. In 2007, the FDA wrote new rules to improve the quality of manufacturing for dietary supplements and the proper listing of supplement ingredients. But these rules do not address the safety of the ingredients or their effects on health.
Most such supplements have not been tested to find out if they interact with medicines, foods, or other herbs and supplements. Even though some reports of interactions and harmful effects may be published, full studies of interactions and effects are not often available. Because of these limitations, any information on ill effects and interactions below should be considered incomplete.

Several medical case reports have described serious side effects in people with cancer who have taken cesium chloride, including life-threatening problems with heart rhythm, seizures, loss of consciousness, and electrolyte imbalances. Cesium appears to take the place of potassium, a common element in the body, which can cause many of these problems.

Newer reports have suggested that it can take weeks or even months for cesium to cause some of the more severe heart problems. A 2009 report described a woman who had been taking 3 grams of cesium each day for a few months. Even though she also took electrolytes and potassium, she started losing consciousness due to interruptions in heart rhythm. Medical treatment included electrical shocks to the heart and extra potassium, but even after 6 days without cesium her potassium level remained low. With a half-life over 6 weeks (meaning that it takes more than 42 days for the body to get rid of half a dose), cesium stays in the body a long time.

Consuming large amounts of cesium, or taking cesium over several weeks or months, can result in nausea, diarrhea, disturbed heart rhythm, loss of consciousness, or even death.

Based on results of animal studies, women who are pregnant or breast-feeding should avoid taking cesium chloride supplements.

Relying on this type of treatment alone and avoiding or delaying conventional medical care for cancer may also have serious health consequences.

To learn more

More information from your American Cancer Society

The following information on complementary and alternative therapies may also be helpful to you. These materials may be found on our Web site (www.cancer.org) or ordered from our toll-free number (1-800-227-2345).

Dietary Supplements: What Is Safe?

The ACS Operational Statement on Complementary and Alternative Methods of Cancer Management

Complementary and Alternative Methods and Cancer

Placebo Effect

Learning About New Ways to Treat Cancer

Learning About New Ways to Prevent Cancer


Cesium chloride. Memorial Sloan-Kettering Cancer Center Web site. http://www.mskcc.org/mskcc/html/69172.cfm. Accessed April 11, 2011.

Dalal AK, Harding JD, Verdino RJ. Acquired long QT syndrome and monomorphic ventricular tachycardia after alternative treatment with cesium chloride for brain cancer. Mayo Clin Proc. 2004:79(8);1065-1069.
Erratum in: Mayo Clin Proc. 2004:79(9);1215

El-Domeiri AA, Messiha FS, Hsia WC. Effect of alkali metal salts on sarcoma I in A/J mice. J Surg Oncol. 1981;18:423-429.

Lyon AW. Mayhew WJ. Cesium toxicity: a case of self-treatment by alternate therapy gone awry. Ther Drug Monit. 2003;25:114-116.

Messiha FS. Developmental toxicity of cesium in the mouse. Gen Pharmacol. 1994;25:395-400.

Messiha FS, Stocco DM. Effect of cesium and potassium salts on survival of rats bearing Novikoff hepatoma. Pharmacol Biochem Behav.1984;21 Suppl 1:31-34.

Neulieb R. Effect of oral intake of cesium chloride: a single case report. Pharmacol Biochem Behav.1984;21 Suppl 1:15-16.

Pinsky C, Bose R. Pharmacological and toxicological investigations of cesium. Pharmacol Biochem Behav.1984;21 Suppl 1:17-23.

Pinter A, Doran P, Newman D. Cesium-induced torsades de pointes. New Engl J Med. 2002:346;383-384.

Samadani U, Marcotte P. Zero efficacy with cesium chloride self-treatment for brain cancer. Mayo Clin Proc. 2004;79:1588.

Sartori HE. Nutrients and cancer: an introduction to cesium therapy. Pharmacol Biochem Behav. 1984;21 Suppl 1:7-10.

Wiens M, Gordon W, Baulcomb D, et al. Cesium chloride-induced torsades de pointes. Can J Cardiol. 2009 Sep;25(9):e329-31.

Note: This information may not cover all possible claims, uses, actions, precautions, side effects or interactions. It is not intended as medical advice, and should not be relied upon as a substitute for consultation with your doctor, who is familiar with your medical situation.

Last Medical Review: 08/15/2011
Last Revised: 02/28/2014