Caffeine is a drug I have a love/hate relationship with. If I haven't had any in a few days and have a moderate dose of 150-200mg, it can be great for a few hours. I get a wonderful manic energy, some euphoria, and the ability to devote myself to a task.
If I space my usage out by a few days and keep the dose reasonable, it can be a really good drug. Used in that manner, I find three drawbacks, slight jitteriness, mild to moderate nausea from about the third to sixth hour, and inability to sleep until 8 hours.
The problems occur when I go further. If I allow myself to get in the habit of using it daily, I experience minor craving accompanied by moderate lethargy when it wears off, the withdrawl lasting for usually 2 days. If I exceed about 200mg, I get moderate to fairly strong nausea from about 2 hours till 10 hours (I've come very close to puking a couple of times). Having too much caffeine makes me very uncomfortable. I feel like I just have to scream or release the energy somehow, but strangely I don't get the manic energy that I do at the lower doses, but rather sit or stand around, feeling overly wired and nauseaus.
The most caffeine I've ever been on was about 700mg. I had to urinate constantly and didn't feel like doing anything but lie down and feel very tense. Worse yet, I was in a setting that was very uncomfortable (emotionally painful actually) and the caffeine exacerbated the problem.
I love a big cup of coffee right at the start of an LSD trip because it gives me lots of fun energy and puts me in a good mood. I also enjoy caffeine and marijuana. The caffeine helps combat the drowsiness of pot while the pot eliminates the nausea and tenseness I get from caffeine.
For a long time, I would tell myself that I would quit caffeine permanantly, but keep returning to it. I've accepted the fact that I really like stimulants, and I've decided not to try amphetamines because I would probably get addicted to them. Caffeine, though addictive, exhibits some anti-addictive mechanisms in that I feel really shitty when I have too much and get quite nauseous too.
For the record, my favorite dose/method of caffeine ingestion is to brew about 12 ounces of very strong coffee and add 1 oz whole milk, or 1/2 oz cream or half-and-half if available.
