drugs that affect the skin & mucous membranes

• fatty or oily substancces applied to soothe the skin or mucous membranes.
• petrolatum, rosewater oinment, lanolin

protective agents used primarily to alleviate irritation, particularly of mucous membranes and abraded tissue.

• precipitate protein but ordinarily do not penetrate beyond cell surfaces, so the cell remains viable. 
• salts of aluminum, zinc, alcohols

• produce irritation:
• counter irritants-used to irritate in broken skin to relieve deep pain in muscles joints and bruises
• rubefacients-produce local vasodilation,redness, and a feeling of warmth 
• vesicants-cause strong irritation; blisters may be produced if used in high concentration or long periods.

• cause sloughing of hardened epithelium. used to cauterize ulcers and to destroy excess tissue such as calluses and warts. 
• benzoic and salicylic acids, resorinol, lactic acid

• substances that cause a loss of sensation. applied directly or injected
• benzocaine - throat lozenges and topical preparations