is there an upper limit to tolerance?

[gib65]

When the brain develops a tolerance to certain drugs, is there a limit to how tolerant it can be? I ask because I develop a serious tolerance to caffein, and when that happens, it doesn't matter how much coffee I drink, I'm just crashing. I have to abstain from it for a week to get back to my normal level (after which point, one cup of coffee will send me buzzing for 18 hours). The crash usually last about 3 days, but that's usually only after several days of drinking coffee. If I have a few cups on just one day of the week, I don't notice much of a crash at all afterwards.

 

For this reason, I'm always perplexed how others can go day after day drinking 3 or 4 cups of coffee and aparently function normally. No one I've asked has ever reported experiencing crashes due to their tolerance being too high. So I'm wondering if there's such a thing as one's tolerance reaching an upper limit so that they can drink however many cups of coffee they need to stay alert and their tolerance doesn't go any higher. That way, we could say they've reached their daily amount which will be the same amount they'll need day after day from here on in. Maybe my daily amount is just extremely high (I've heard of people who need upwards of 10 cups of coffee to keep them going through the day).

[CharonY]

Well, it appears that you are actually sensitive against caffeine. Especially given the fact that it takes relatively long to get the caffeine out of your system. In other words, you need less to get the maximum effect (which will be individually different) whereas others require more to get the same symptoms. There are of course also those that have a high caffeine resistance (no crash but no buzz either).

Edited September 1, 2009 by CharonY