Very high potassium levels, also known as hyperkalemia, are commonly indicative of kidney failure, states Healthline. Normal blood potassium levels range between 3.6 and 5.2 millimoles per liter, explains Mayo Clinic. Having a blood potassium level higher than 7.0 is considered dangerous and requires immediate medical intervention.
When kidney function is impaired, excess potassium in the blood is not removed from the body effectively, causing it to build up in the blood. The excess potassium may initially occur as a result of Addison's disease; tumors; burns over a large area of the body; severe bleeding from stomach or intestines; disorders that cause blood cells to burst, such as hemolytic anemia; and damage of cells due to untreated seizures, drug or alcohol abuse, infection and chemotherapy, according to MedlinePlus.
Certain drugs may also hinder the kidneys' ability to remove potassium, explains WebMD. These include antibiotics, such as penicillin G and trimethoprim; azole antifungals used to treat vaginal yeast infections; blood pressure drugs, such as ACE inhibitors and beta blockers; Heparin; nonsteroidal anti-inflammatory medications; potassium supplements; and potassium-sparing diuretics, such as triamterene, amiloride and spironolactone.
Symptoms associated with hyperkalemia include nausea; slow, weak or irregular heartbeat; and sudden collapse due to very slow heart or stopped pulse, notes MedlinePlus. Sometimes no symptoms are present.