Why do potassium supplements contain only 99 mg?

Many US makers limit potassium supplements to 99 mg per serving because of rules for potassium medicines.^[1] 99 mg is about 2% of the US Daily Value of 4,700 mg.^[1] There are two reasons:

• The FDA ruled that some potassium chloride medicines with more than 99 mg are not safe, because they were linked to injuries of the small bowel.^[1]
• The FDA requires a warning on some potassium salts with more than 99 mg per tablet.^[1]

The FDA has not ruled whether supplements above 99 mg need such a warning.^[1] In the US, 12% of people take a supplement with potassium, and it adds only 87 mg a day on average.^[1] For comparison, one medium banana has 422 mg.^[1]