SWIM still enjoys the feeling he gets from Ambien as a sedative and relaxant, but he's built up a tolerance to its sleep inducing effect. Time was that he could take 10mg and conk out fast no matter what (10 cups of coffee wouldn't stop it, even a hit of speed wouldn't stop it). Now it's possible that he'll lay there in bed subconsciously but successfully fighting off its effects, no matter how high the dosage. Or he'll go into a light doze with no REM sleep, and have to redose 2.5 hours later to maintain even that. Bummer, eh?
So what works well for SWIM? Melatonin. 6mg minimum to about 12mg max taken orally with vitamin B6 pretty reliably puts him to sleep 30 minutes later, even if it's not his usual bed time. What's more, he sleeps *well* on it and rarely (if ever) wakes up after a few hours, which tends to happen on non-CR formulations of Ambien.
What *doesn't* work at all? Antihistamines... uggh. Half the time he's more agitated on 'em than drowsy, out of bed in a half hour and feeling like sh*t.