The short version
16 companies supply this market — deep enough that no single failure threatens the supply. The generic price has fallen 38% in a year, to $0.5493 per unit — and generics that get this cheap tend to get abandoned rather than defended. The brand (Amitiza) runs $6.46 per unit — 11× more. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
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