Editing Partition coefficient (section)

==== Pharmacodynamics ====
In the context of [[pharmacodynamics]] (how the drug affects the body), the [[hydrophobic effect]] is the major driving force for the binding of drugs to their [[receptor (biochemistry)|receptor]] targets.<ref name="Eisenberg">{{cite journal | vauthors = Eisenberg D, McLachlan AD | title = Solvation energy in protein folding and binding | journal = Nature | volume = 319 | issue = 6050 | pages = 199–203 | year = 1986 | pmid = 3945310 | doi = 10.1038/319199a0 | bibcode = 1986Natur.319..199E | s2cid = 21867582 }}</ref><ref name="Miyamoto">{{cite journal | vauthors = Miyamoto S, Kollman PA | title = What determines the strength of noncovalent association of ligands to proteins in aqueous solution? | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 90 | issue = 18 | pages = 8402–6 | date = September 1993 | pmid = 8378312 | pmc = 47364 | doi = 10.1073/pnas.90.18.8402 | bibcode = 1993PNAS...90.8402M | doi-access = free }}</ref> On the other hand, hydrophobic drugs tend to be more toxic because they, in general, are retained longer, have a wider distribution within the body (e.g., [[intracellular]]), are somewhat less selective in their binding to proteins, and finally are often extensively metabolized. In some cases the metabolites may be chemically reactive. Hence it is advisable to make the drug as hydrophilic as possible while it still retains adequate binding affinity to the therapeutic protein target.<ref name="Pliska">{{cite book | vauthors = Pliska V, Testa B, Van De Waterbed H   |title = Lipophilicity in Drug Action and Toxicology |publisher = John Wiley & Sons Ltd. |year = 1996 |location = New York  |pages = 439 pages |isbn = 978-3-527-29383-4 }}</ref> For cases where a drug reaches its target locations through passive mechanisms (i.e., diffusion through membranes), the ideal distribution coefficient for the drug is typically intermediate in value (neither too lipophilic, nor too hydrophilic); in cases where molecules reach their targets otherwise, no such generalization applies.{{citation needed|date=March 2016}}