[From a Medical Doctor friend of erowid.]
I have detoxed two heavily GHB addicted individuals as outpatients using a benzo (Klonopin), Neurontin (fairly quickly getting up to 2700 to 3000mg), and some Clonidine.
Subjectively the people complained and felt miserable, but objectively vital signs and the rest looked pretty good. It seemed to take two or three weeks.
Some people seem to get addicted surprisingly quickly. I believe that alcohol and other sedative-hypnotics are often more difficult and complicated to manage in terms of the withdrawal process, but that always involves people who have practiced dependency producing patterns for many months or years-- people seem to get dramatically dependent on GHB within just a couple of months (taking it day and night) and suffer through the detox.