"i just recently started taking it (a little less than 2 weeks ago). the first day i was very giddy and kept getting a tingly feeling from my head to my toes.  than it stopped after the second day but i did experience the hot sweats, loss of appetite, nausea and lack of sleep. the sleep was the worst thing! i woke up almost every hour every night for 2 weeks straight!  i was either waking up and feeling wired or waking up because of the hot sweats and i&#039;m only 23!  if you want advice, do not take caffeine until some of these side effects go away because it will make you way more wired than usual and you&#039;ll feel very uncomfortable.  also, do not drink alcohol. 1 sip of wine and felt dizzy for at least an hour!"