I'm not sure if you thought the hives were a side effect of decadron or from eating shrimp. I think it more likely the hives are related to a shellfish allergy. Even if your husband was never allergic to shellfish before, he may be now. I'd use extreme caution in eating shellfish in the future.
To be sure, though, your husband may want to consult with his doctor.
To your health,
Kathi
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