This is from a previous post of mine:

Potassium is restricted to less than 100 mg per tablet for over-the-counter use because it has the potential to irritate the stomach, not because of cardiac risk. Supplements will often have an "enteric" coating to slow absorption for this reason. Don't crush or chew the pill and make sure you take it with a full glass of water to ensure that it doesn't get lodged in your throat.

Potassium is found in amounts much larger than 100mg per portion of many foods, and no cardiac event imminent from consuming them.

• 1 can (7 oz/ 200g) sockeye salmon - 1,391mg
• 1 medium california avocado - 1,097mg
• 1/2 pkg (5 oz/ 140g) spinach - 824mg
• 1 medium stalk broccoli - 526mg
• 1/3 cup natural sunflower seed kernels - 331mg
• 1/2 cup canned diced tomatoes - 290mg
• 1 Tbsp dutch process unsw. cocoa powder - 254mg
• 2 Tbsp peanut butter - 214mg
• 1/8 tsp potassium-salt substitute - 325 to 500mg
  
  (all values from our carb counter tool, which is based on the current USDA)

Adults require 2,500 to 3,500 mg of potassium daily - depending on physical size, activity level and climate. Need will be even greater when there is increased water losses from the body, such as sweating due to high temperature or vigorous exercise, increased urination, vomiting and/or diarrhea. High blood sugars with high insulin levels will force potassium into the cells, thus causing levels in the blood to drop.

In general, potassium is acquired from the food we eat, as well, not all gets excreted from the body .. some is retained and recirculated. Healthy kidneys in concert with healthy adrenal glands will prevent blood levels from getting too high, but are less efficient at preventing levels from getting too low, unfortunately.

Conditions which can lead to too high potassium levels: kidney failure, adrenal failure, and large injuries such as severe burns or where there is crushing or internal bleeding (potassium is released from the injured cells and dumped in a sudden large amount into the bloodstream). Also, certain medications can cause the kidneys to retain potassium ... some diuretics such as Spironolactone or Aldactone, used to treat high blood pressure, and some heart and blood pressure medications called ACE-inhibitors, such as captopril, enalapril, Altace, Capoten, Lotensin .. CHECK WITH YOUR DR. OR PHARMACIST BEFORE USING SALT SUBSTITUTE OR SUPPLEMENTS WITH POTASSIUM.

Doreen