It depends on the user. I personally find promethazine to be a bit too sedating. Diphenhydramine works wonderfully and its OTC in the U.S. (promethazine isn't OTC in the U.S.). Doxylamine is another winner. Hydroxyzine is always really effective. Don't forget chlorpheniramine (CPM) either. It's under-rated IMO.
But yes, I would go with CPM, DPH or doxylamine if I had a choice between the three. Promethazine is good but I would be using hydroxyzine (if either of those were OTC where I live).
That's interesting, i have some Chlorpheniramine 4mg tabs at home in my medicine drawer but ive never tried using them, the only time i tried using Doxylamine was not for potentiation purposes but to help me sleep on a flight, i started out at 25mg waited, felt nothing, dosed another 25mg, waited and felt nothing, so i then dosed another 50mg waited and still felt nothing so i ended up eating the remaining 6x25mg tabs, so in total i dosed 250mg, i did then feel something, infact i felt a lot! And it wasn't pleasant!
It also didnt sedate me.
The only time ive ever used Hydroxyzine was also for flight anxiety, it worked pretty much the same as Doxylamine, i started low and slowly worked my doseage upwards as i wasnt feeling anything from it, and then by the time i did feel something i had obviously taken too much and just felt awful and once again was not sedated.
As far as im aware all the antihistamines mentioned are available over the counter here in the U.K with the exception of Hydroxyzine, which im not sure either way whether it is or not, i may try Doxylamine and Hydroxyzine at sensible doses for Opiate potentiation in the future just to see how they compare to Diphenhydramine and Promethazine.
Does anyone know if it's safe to take Diphenhydramine and Chlophenamine in the same day? For example i took some Oxy earlier (around 6 hours ago) preceded by 50mg Diphenhydramine, would it be safe and/or effective if i was to take some Chlorphenamine within the next few hours before another dose of Oxycontin?
I know Diphenhydramine has a half-life of around 9-12 hours and Chlorpheamine has a half-life of around 24 hours, and from what i read it is not as sedating as Diphenhydramine... also does anybody know a rough comparison in doses between the two? As i mentioned i usually take 50mg Diphenhydramine around 30-45 minutes before my Oxy, yet the Chlorphenamine comes in 4mg tabs.... how many mg's would be equivilant? I also guess i should take it around 30-45 minutes before my Oxy dose...
Thanks for any help.