Pro-drugs of ibuprofen comprising a thiopropionate or propionamide moiety, wherein the amino group is tertiary and protonated. This positively charged amino groups of these pro-drugs not only largely increases the solubility of the drugs, but also bonds to the negative charge on the phosphate head group of membranes and pushes the pro-drug into the cytosol. Diethylaminoethyl 2-(p-isobutylphenyl) propionate.AcOH for example diffuses through human skin 250 times faster than ibuprofen itself and 125 times faster than ethyl 2-(p-isobutylphenyl) propionate. In plasma, more than 90% of these pro-drugs can change back to the drug in a few minutes. The prodrugs can be used medicinally in treating any ibuprofen-treatable conditions in humans or animals and be administered not only orally, but also transdermally for any kind of medical treatments and avoid most of the side effects of ibuprofen, most notably GI disturbances such as dyspepsia, gastroduodenal bleeding, gastric ulcerations, and gastritis. Controlled transdermal administration systems of the prodrug enables the ibuprofen to reach constantly optimal therapeutic blood levels to increase effectiveness and reduce the side effects of ibuprofen.