I'm not sure if you're recommending GHB to others to use as a comedown drug, Renz, but if you are, it's far too addictive. I know your intentions are good, but there are other drugs that can work in a similar fashion to GHB without being as addictive, like Phenibut or Baclofen. However, the main benefit is that GHB causes dopamine antagonism, which is perfect for coming down off of stimulants, but that antagonism can be achieved with other drugs, not necessarily antipsychotics.
Thanks for giving us your experiences on DPH as a comedown drug, I will recommend it to others who have trouble sleeping after taking stims. I agree with NT, though, that the anticholinergenic effects of DPH could mess with your heart rate and dry you out, perhaps Hydroxyzine is a better choice for this, lacking significant anticholinergenic actions, and instead acting as a sedative through D2 (dopamine receptor) antagonism and antiserotonergic actions, like 5-HT2C antagonism.
I recommend every stimulant user taking 1mg melatonin at night. Not only is it an extremely powerful antioxidant, but it tells your body it's time to sleep by affecting the circadian rhythm, rather than just knocking you out like antihistamines. Doxylamine could be a better OTC sedative than DPH, though, as it has more powerful anticholinergenic actions, less Dopamine agonism that would tend to keep you awake, and it tends to produce less of a hangover, despite its beneficially longer half life.
Also, every stimulant user should take 300mg chelated Magnesium before bed on an empty stomach, and 150mg on an empty stomach before dosing amphetamines. Beware, though, Mg can make your pH levels more basic, potentiating amphetamines. I offset this pH change with the 250mg Vitamin C in a Super B Complex after breakfast. Zinc on a full stomach after dosing amps is another great immune booster and REM-sleep increaser, and potassium supplementation is also beneficial by reducing risk of stim-induced strokes.
