The short version
10 companies supply this market — deep enough that no single failure threatens the supply. The generic price has fallen 46% in a year, to $10.53 per mL — and generics that get this cheap tend to get abandoned rather than defended. The brand (Alrex) runs $58.03 per mL — 3.3× more. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
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