For whatever reason I have always been under the assumption that the half life of 50mg of Naltrexone was 4 hours. In other words, you need to do your drinking within that four hour time frame (which is inclusive of the 1 hour wait time) or take more. I exchanged a couple of emails with Roy Eskapa and I quote, "Naltrexone 50 mg will cover the average person for 24 hours. The one hour wait time would therefore allow 23 hours drinking time -- however if someone starts early in the morning and finds he is drinking at say 9 or 10 pm then it may be advisable to take another 50 mg naltrexone. This would have to be checked by a medical doctor. So if you take a tablet wait an hour then drink for 3 or 4 hours if you feel the compulsion to drink after 6 hours you need not take another tablet. So this is unlikely to be impeding your progress.". Anyone know why there is this apparent disparity between I thought everyone was doing and what the Master says? maybe I have just been confused all along. I am seeing nasty spikes in my intake in the last couple of weeks despite being on the program for almost 5 months.

from the TCFA book:

"The activity of naltrexone is believed to be due to both parent and the 6-β-naltrexol metabolite. ... The mean elimination half-life (T-1/2) values for naltrexone and 6-β-naltrexol are 4 hours and 13 hours, respectively"

even if you ignore the 6-β-naltrexol with the longer half-life, after 4 hours you're going have the equivalent amount of Nal in your bloodstream as if you'd just taken 25mg, & after 8 hours as if you'd just taken 12.5mg. as the various Doc's advise that 50mg should cover you for 24 hours, then in all probability considerably less than 12.5mg is enough to saturate the receptors for a good few hours

-badger

I have taken 25mgs and it was definitely not sufficient.