i've found that drinking can help to lower my tolerance. if i have a few beers, (tipsy, not intoxicated), then smoke, i get a really really tired slow high, and if i have a few beers after toking i feel it brings the high back. also, pot cancels out the bad after effects of alcohol, atleast for me, so i like to try smoke a doob before bed if i have to wake up in the A.M