**Potassium is an electrolyte found in every cell of your body.
A certain amount of potassium is required by all cells, but too much can be harmful and even fatal.
** In healthy people, a potassium overdose rarely occurs unless a large number of potassium supplements are consumed, either intentionally or by accident. But in people with other reasons for an elevated potassium -- such as certain medical disorders or medications -- even usual dietary intake of potassium may act as an overdose and lead to high potassium levels 1.
Potassium overdose will generally cause no symptoms until the blood potassium rises above 6.5 or 7.0 meq/L, according to “StatPearls.” When present, symptoms typically involve the nerves, heart or digestive system.
“Merck Manual” cautions that high potassium levels often produce no symptoms until potentially life-threatening heart beat abnormalities appear 126. Because of this, seek immediate medical care if you suspect a potassium overdose, even if you have no symptoms.
**Excessive potassium interferes with the normal conduction of electrical impulses in nerves.
Because muscles contract only when stimulated by nerves, impaired nerve function leads to muscle weakness. This weakness often begins in the legs. ** Breathing muscles, such as the diaphragm, may also become weak, reducing the ability to breathe and causing shortness of breath.
Tingling sensations can occur when sensory nerves are affected by high potassium levels 1. Tingling tends to be especially prominent in the arms and legs. Confusion and even coma can occur when potassium levels are very high 1.
- Excessive potassium interferes with the normal conduction of electrical impulses in nerves.
- Because muscles contract only when stimulated by nerves, impaired nerve function leads to muscle weakness.
Glycerine Vs. Glycol
Heart beat abnormalities are the most dangerous effect of a potassium overdose. High potassium interferes with normal conduction of electrical impulses in the heart. This leads to a slow heart beat and eventually to cardiac arrest and death if potassium levels continue to rise 1.
According to the medical textbook “Brenner and Rector’s The Kidney E-Book,” subtle changes in the electrocardiogram begin to appear at an early stage, when the blood potassium level rises above 5.5 meq/L 36. At potassium levels above 8.0 meq/L, the heart beat will often begin to slow 1. This may cause palpitations, weakness, dizziness, lightheadedness and fainting. Chest pain and shortness of breath may also occur, especially in people with heart disease.
- Heart beat abnormalities are the most dangerous effect of a potassium overdose.
Digestive Tract Symptoms
Hyperkalemia from any cause may produce nausea and vomiting, according to Medscape 6. Potassium supplements can also directly irritate the stomach and intestines, especially when consumed in large amounts.
This irritation may cause nausea, vomiting and diarrhea. Sometimes, open sores -- called ulcers -- occur as well. Rarely, the ulcers will be deep enough to extend through the wall of the small intestine, causing a perforation, according to an article published in “Journal of Toxicology -- Clinical Toxicology” in October 2001.
- Hyperkalemia from any cause may produce nausea and vomiting, according to Medscape.
What Does a High Potassium Blood Level Mean?
If you think you may have taken a potassium overdose, seek immediate medical attention.
To avoid a potassium overdose in the future, only take potassium supplements under the direction of your doctor.
Make sure you follow all instructions regarding the amount to take and when to return for follow-up blood tests. Do not make any changes in your diet, such as increasing your intake of potassium-rich foods or potassium-containing salt substitutes, without asking your doctor.
If you have a medical condition or are taking medications that tend to raise blood potassium levels, your doctor may recommend limiting your potassium intake 1.
Reviewed and revised by Mary D. Daley, M.D.
- If you think you may have taken a potassium overdose, seek immediate medical attention.
- If you have a medical condition or are taking medications that tend to raise blood potassium levels, your doctor may recommend limiting your potassium intake 1.
Glycerine Vs. Glycol
What Does a High Potassium Blood Level Mean?
Can Too Much Potassium Cause Liver Problems?
Does Potassium Aid in Weight Loss?
Does Potassium Thicken Your Blood?
Hand Tremors & Potassium
Shin Pain Caused by Low Potassium
What Are the Dangers of High Potassium?
Can Too Much Potassium Cause Muscle Cramps?
Symptoms of Low Potassium & Low Bilirubin
- MedlinePlus: High Potassium Levels
- Merck Manual Professional Version: Hyperkalemia
- Brenner and Rector’s The Kidney E-Book; Karl Skorecki, et al.
- Journal of Toxicology -- Clinical Toxicology: Sustained-Release Potassium Chloride Overdose
- StatPearls [Internet]: Hyperkalemia
- MedScape: Hyperkalemia
- National Institutes of Health: Potassium
- Potassium. Office of Dietary Supplements. National Institutes of Health
- Lambert H, Frassetto L, Moore JB, et al. The effect of supplementation with alkaline potassium salts on bone metabolism: a meta-analysis. Osteoporos Int. 2015;26(4):1311-8. doi:+10.1007/s00198-014-3006-9
- Chatterjee R, Slentz C, Davenport CA, et al. Effects of potassium supplements on glucose metabolism in African Americans with prediabetes: a pilot trial. Am J Clin Nutr. 2017;106(6):1431-1438. doi:10.3945/ajcn.117.161570
- Potassium. Fact Sheet for Consumers. Office of Dietary Supplements. National Institutes of Health
- Health Claim Notification for Potassium Containing Foods. US Food and Drug Administration
- Aburto NJ, Hanson S, Gutierrez H, Hooper L, Elliott P, Cappuccio FP. Effect of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analyses. BMJ 2013;346:f1378.
- Academy of Nutrition and Dietetics. What Is Potassium?
- ConsumerLab.com. Potassium Supplements Review.
- Curhan GC, Willett WC, Rimm EB, Stampfer MJ. A prospective study of dietary calcium and other nutrients and the risk of symptomatic kidney stones. N Engl J Med 1993;328:833-8.
- Curhan GC, Willett WC, Speizer FE, Spiegelman D, Stampfer MJ. Comparison of dietary calcium with supplemental calcium and other nutrients as factors affecting the risk for kidney stones in women. Ann Intern Med 1997;126:497-504.
- D’Elia L, Barba G, Cappuccio FP, Strazzullo P. Potassium intake, stroke, and cardiovascular disease a meta-analysis of prospective studies. J Am Coll Cardiol 2011;57:1210-9.
- O’Neil C, Keast D, Fulgoni V, and Nicklas T. Food sources of energy and nutrients among adults in the US: NHANES 2003-2006. Nutrients. 2012;4:2097-120. DOI: 10.3390/nu4122097.
- Stone M, Martyn L, and Weaver C. Potassium intake, bioavailability, hypertension, and glucose control. Nutrients. 2016;8: E444. DOI: 10.3390/nu8070444.
- U.S. Food and Drug Administration. Health Claim Notification for Potassium Containing Foods.
- Weaver CM. Potassium and health. Adv Nutr 2013;4:368S-77S.
- Yong Sun, et al. Dietary potassium regulates vascular calcification and arterial stiffness. JCI Insight. 2017;2(19):e94920.
Natalie Overstreet is a registered, licensed dietitian who began writing professionally in 2013. She specializes in nutrition for LIVESTRONG.COM. She received a Master of Science in human sciences from Stephen F. Austin State University, emphasizing in food, nutrition and dietetics. Overstreet currently works as a clinical dietitian and health educator in East Texas.