Sulphadimidine

Sulphadimidine is the alternative British spelling for sulfadimidine, itself an alternative term for sulfamethazine, the widely used veterinary sulfonamide. The existence of parallel American (sulf-) and British (sulph-) spellings for the whole sulfonamide family is a persistent source of confusion in residue records, prescriptions, and regulatory documents. Both spellings denote the identical compound with identical pharmacology, withdrawal periods, and residue limits. Standardizing on one spelling within a quality system avoids misidentification of this important class of animal medicines. Residue surveillance programmes routinely cross-reference both spellings when compiling monitoring data.