HELP - Lipophilic drugs and Retention Characteristics

[narconon]

Hi,

My question regards drugs (primarily psychotropics). It is my understanding
that many types of drugs can become bound to lipids, either within
adipocytes or somehow to lipid membranes. I am a chemical dependency
counselor and there is a theory that some drug cravings are caused by
re-release of these bound drug residues into the bloodstream when the
plasma levels of these drugs (such as cocaine or heroin) fall beyond a
certain level. 

Can anyone give me a good explanation of this binding process and details
on it? Does anyone know of research being done in this area?

Thanks,
Larry Lewyn