Inden omstilling til Insulin Human Winthrop Comb 50 anbefales det at foretage en intradermal hudtest på de patienter, der er allergiske over for animalsk insulin, da disse patienter kan udvikle immunologiske krydsreaktioner.
In patients with an allergy to animal insulin intradermal skin testing is recommended prior to a transfer to Insulin Human Winthrop Comb 50, since they may experience immunological cross-reactions.