I take melatonin sometimes when my sleep cycle is off. It's really helpful for correcting it, but I don't like that, even with small doses, I feel vaguely like I'm walking around in a dream world until noon or so the next day.
While we're sharing our anecdotes, at the suggestion of a coworker I took 5mg melatonin each night for a few months, which worked wonders for actually staying asleep at night. In my experience the important part was taking it at the same time each night to mimick how the brain naturally releases the hormone. I never, for example, used it to sleep during the day after an all-night flight, just to regulate my day/night cycle.
> I feel vaguely like I'm walking around in a dream world until noon or so the next day.
How small are your small doses? Melatonin is often sold in 5 mg tablets, but Dr. Andrew Weil [1] recommends 2.5 mg at bedtime as an occasional dose and a much lower dose, 0.25 to 0.3 mg, for regular use.
I was also going to recommend melatonin. I have a hard time falling asleep, and Melatonin really helps avoid the late night brain rush that keeps me awake. Though I'm honestly not clear on all the side-effects.
This is not a particularly good argument. After all, the body also produces opiates naturally, but it's generally not a good idea to take them long term.
Note: we cut pill in half for our 10 yr old. It was a life changer for us!