Salt substitutes are edible products designed to taste similar to table salt, which is mostly sodium chloride. They usually contain mostly potassium chloride, which when consumed increases potassium intake. Because excess potassium intake can cause potentially fatal hyperkalemia, it is advisable to check with one's physician and pharmacist before using salt substitutes based primarily on potassium chloride. This is generally not a problem because the RDA of potassium is higher than that for sodium, yet a typical person consumes less potassium than sodium in a given day.
Various diseases and medications may decrease the body's excretion of potassium, thereby increasing the risk of hyperkalemia. If you have kidney failure, heart failure or diabetes, you should not use a low salt variety without medical advice. A manufacturer, LoSalt, has issued an advisory statement. that people taking the following prescription drugs should not use a salt substitute: Amiloride, Triamterene, Dytac, Spironolactone, Aldactone, Eplerenone, and Inspra.
- LoSalt Advisory Statement (PDF)