Melatonin is not a sedative...
if 3 mg has done nothing then taking more is not going to do anything at all. It has a strange response curve, as stated above, if a small dosage hasn't helped, taking more will not help either 5mg, 50mg, 500mg... 1mg-3mg is all i'd ever take. Don't buy into the "Extra Strength" 10mg formulas you can buy... they are a crock.
Melatonin is a natural hormone that affects your body's circadian rhythm (think 'internal clock'). It is best used to help reset the timing on when you feel like its time for bed. For instance after taking a long plane flight you may be aided by melatonin in helping reset your sleep schedule...
Granted some people do take melatonin on a regular basis for sleep - its certainly not what you want to help sleep after amphetamines. It just doesn't work that way pharmacodynamically. Its far different from taking benzos or ambien or diphenhydramine , the regular types of sedatives...
