The short version
4 companies supply this market — a reasonable cushion if one runs into trouble. The generic price has fallen 33% in a year, to $2.19 per gram — and generics that get this cheap tend to get abandoned rather than defended. The brand (Dymista) runs $9.14 per gram — 4.2× more. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
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