The orally administered carboxylic acid analgesics salicylic acid, aspirin, ibuprofen, naproxen and ketoprofen are known to cause stomach bleeding. Endeavoring to synthesize fat soluble derivatives of these analgesics for potential transdermal administration, we have esterified them with the primary alcohol derivatives of the major fatty acids in human fat; namely, oleyl alcohol (a derivative of oleic acid aka (Z)-octadec-9-enoic acid, 46% of human fat) and cetyl alcohol (aka 1-hexadecanol, a derivative of palmitic acid, aka hexadecanoic acid, 25% of human fat). We have also attempted to di-esterify these analgesics with the water soluble diol, polyethylene glycol�molar mass 8000 (PEG 8000); these results are currently inconclusive. PEG 8000 is soluble in some fats. Derivatives of this polymer are used as orally ingested laxatives and in skin creams/lotions. Thus far, we have studied the structures of these compounds by thin layer chromatography, and infrared spectroscopy. Attempted methods, successful methods, and characterization of structure will be discussed.