The short version
17 companies supply this market — deep enough that no single failure threatens the supply.
Market view
43 marketed package NDCs · 17 active manufacturers
Most dispensed: Kit · #90 boxs/carton / 1 kit in 1 box * 1 for suspension in 1 packet * 1 for suspension in 1 packet · 500 mg · Tablet · #1 bottle/carton / 250 tablet in 1 bottle
17 companies supply this market — deep enough that no single failure threatens the supply.
Other molecules FDA puts in Nitrogen Binding Agent, with whether each is in shortage right now. Same class is not the same drug — substitution is a clinical decision, and this is a supply picture, not a recommendation.
Expand a strength to see its dosage forms, then package sizes, then each manufacturer and NDC. Click an NDC for its full detail page.