Aldehyde, Ketone, Carboxylic Acid Aldehyde: Aldehyde is an organic compound which contain formyl group. This functional group, in its structure R-CHO, consist of carboxyl centre bonded to R group and hydrogen.
1 Infections, bites and stings, infestations, chronic diseases, allergic reactions, sun exposure, and dry skin are among the numerous causes of itching.  Anti-itch creams and lotions containing camphor, menthol, phenol, pramoxine (Caladryl, Tronolane), diphenhydramine (Benadryl), or benzocaine can bring relief.
1 Topical creams (for example, calamine lotion) may help reduce itching. 2  Antiviral medications, such as acyclovir (Zovirax), valacyclovir (Valtrex), and famciclovir (Famvir), can decrease the duration of skin rash and pain, including the pain of PHN.