[kstrauser]

Caffeine and gensing have immediate onsets. You know in a small number of minutes whether you’ve had enough or too much. Vitamins usually have a wide range between enough to be useful and enough to harm you, although you’re crazy to take fat-soluble vitamins for a long period without telling your doctor and getting a blood test.

You generally have to take psych meds for quite a few days before determine their effect. If you take too little, you risk your mental health. Take too much? Have fun riding out Seratonin Syndrome!