Chemical compositions and Methods for Enhancing the transdermal penetration of therapeutic agents through the skin. The Chemical compositions and Methods may include combinations of a Fatty Acid that has around 14 or more carbon Atoms and a Second Fatty Acid that has around 10 or fewer carbon Atoms.These compositions are useful for the delivery of therapeutic agents, in particular Drugs difficult to supply, such as the FUSED rings, including Drugs such as ondansetron and large peptides. These compositions can be formulated as transdermal gels, Lotions, creams, patches, sprays or Mists.Claim 1: Composition, characterised in that it comprises: a First Fatty Acid that is oleic acid, Linolenic Acid, linoleic acid, miristol u00e9ico palmitol u00e9ico acid or acid, erucic acid, or a derivative or congener； and a Second Fatty Acid is acid 2 - hi Droxioctan u00f3ico, 4 - oxopentan u00f3ico, propionic acid, valeric acid, acid per u00favico, acetoac u00e9tico acid, alanine,Aspartic acid, asparagine, glutamic acid, Glycine, Valine, or Licina, levulinic acid, or a derivative or congener. Claim: the composition of any of Claims 7 to 9, wherein the therapeutic Agent is one or more of: ondansetron, granisetron, tropisetron, dolasetron, palonosetron, or salts thereof.Claim 21: the use of the composition according to any one of Claims 6 to 20 for the manufacture of a Medicament for treating a disease or condition.Claim 34: a method for forming a composition, characterized in that it comprises, mixing a First Fatty Acid that is oleic acid, Linolenic Acid, linoleic acid, miristol u00e9ico palmitol u00e9ico acid or acid, erucic acid, or a derivative or congener； According to a OJ Fatty Acid that is hidroxioctan u00f3ico acid 2 -, 4 - oxopentan u00f3ico, propionic acid, valeric acid, acid per u00favico,Acetoac u00e9tico acid, alanine, Aspartic acid, asparagine, glutamic acid, Glycine, Valine, or Licina, levulinic acid, or a derivative or congener； and a Therapeutic Agent.Composiciones q
