Potassium bicarbonate is a supplement primarily used to prevent or resolve low potassium levels, known as hypokalemia. Hypokalemia can be caused by an inadequate diet, certain diseases and medications, surgery, and severe or prolonged cases of vomiting or diarrhea, according to Drugs.com. Because potassium supplements can cause high potassium levels, which is more dangerous than low potassium, do not take potassium bicarbonate without first consulting your health care provider.
Digestive side effects are most common with potassium supplements, according to the Linus Pauling Institute, or LPI, at Oregon State University. Some people experience abdominal discomfort, nausea, vomiting or diarrhea. Taking potassium bicarbonate with food can help.
Abnormally high potassium levels, or hyperkalemia, develop when potassium intake surpasses the ability of the kidneys to eliminate it, explains the LPI. Multivitamin supplements with minerals, as well as over-the-counter potassium supplements, contain a maximum of 99 mg per dose. Higher doses are only indicated for preventing and treating hypokalemia. Blood tests are important during potassium supplementation to monitor potassium levels. High potassium levels can cause numb or tingling sensations in the hands or feet, faintness, nausea, sweating and generally feeling ill. Severe hyperkalemia can cause muscle weakness, temporary paralysis, chest pain and seizures. The most serious risk of hyperkalemia, according to the LPI, is an irregular heartbeat, which can lead to a heart attack. People at greater risk for hyperkalemia when taking potassium supplements include individuals with a kidney disorder, Addison's disease, hypoaldosteronism, stomach ulcer, intestinal disorder, and those taking potassium-sparing diuretic medications.
Many medications can interact with potassium bicarbonate, according to Drugs.com. The supplement may not be safe if you take digoxin, certain blood pressure medications such as ACE inhibitors and beta blockers, aspirin and nonsteroidal anti-inflammatory drugs such as ibuprofen and naproxen, or corticosteroids.
Pregnancy and Breastfeeding Risks
The U.S. Food and Drug Administration classifies potassium bicarbonate as pregnancy category C, meaning it may be harmful to an unborn baby. In addition, potassium bicarbonate might transfer into breast milk and could be harmful to a nursing baby.
Although it is unlikely, some people experience an allergic reaction to potassium bicarbonate. Signs as listed by Drugs.com include hives, breathing problems and facial, mouth or throat swelling. An allergic reaction to potassium bicarbonate should be considered a medical emergency.