The invention provides methods of delivering pharmacologic agents linked to an internalization peptide, in which an inflammatory response inducible by the internalization peptide is inhibited by co-administration of an anti-inflammatory or by linking the internalization peptide to biotin or similar molecule. Such methods are premised in part on the results described in the examples whereby administration of a pharmacological agent linked to tat at high dosages is closely followed by an inflammatory response, which includes mast cell degranulation, histamine release and the typical sequelae of histamine release, such as redness, heat, swelling, and hypotension.