I have not much idea about time-release version of melatonin, but melatonin supplementation is generally not about the dosage. Rather, it is to induce the secretion of more melatonin by your body. So, a tiny dosage is required to induce the secretion of melatonin and too much of it will not induce as much.
Effects of low oral doses of melatonin, given 2-4 hours before habitual bedtime, on sleep in normal young humans; Sleep. 1996 Jun;19(5):423-31.
Zhdanova IV, Wurtman RJ, Morabito C, Piotrovska VR, Lynch HJ.
Low oral doses of melatonin raise serum melatonin concentrations to those normally occurring nocturnally and facilitate polysomnographically assessed sleep onset when given at different time points throughout the day, without altering mood or performance on the morning following treatment. In the present study, 12 young healthy volunteers, free of sleep disturbances, received 0.3 or 1.0 mg of melatonin or placebo at 2100 hours, 2-4 hours prior to their habitual bedtime. Polysomnographic recording of overnight sleep began at 2200 hours and continued until 0700 hours the following morning, when subjects were awakened. Sleep onset latency and latency to stage 2 sleep were significantly decreased as a result of melatonin treatment. Neither dose of melatonin significantly altered sleep architecture. Administration of the lower dose of melatonin (0.3 mg) at 2100 hours elevated serum melatonin to levels within the normal nocturnal range (113 +/- 13.5 pg/ml) at the time the sleep test was initiated. Neither melatonin dose caused "hangover effects", as assessed by self-reports or by mood and performance tests administered on the morning following treatment. These observations provide additional evidence that nocturnal melatonin secretion has a sleep-promoting function. They also indicate that an increase in serum melatonin concentrations, within the normal physiologic range, does not significantly alter sleep architecture in subjects with normal sleep who receive the treatment several hours prior to their habitual bedtime.
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Since I have no time to look through the study now, I read an interpretation of the study at ergo-log.com (http://www.ergo-log....ose-0.3-mg.html) and it provides comparative figures as below for easy comprehension of the results;
This bar chart compares the dosages of intake of melatonin to their time to fall asleep.
Administration of 0.3mg of melatonin promotes the fastest time to fall asleep. I can only assume, since other higher dosages aren't tested, that it represented a U-curve that the optimal dosage of melatonin that promotes the fastest time is 0.3mg; too little or too much might disrupt this.
This bar chart compares the dosages of intake to the serum concentration hours later.
Administration of 0.3mg of melatonin induces the greatest concentration of serum concentration hours later. But do take note that this chart is missing comparison with higher doses.
I'm not sure whether does this apply to time-release melatonin that you used, but I'm posting this merely for reference and comparison.
