I voted for DHC but there's not much in it. Just because it it seems to last a couple of hours longer. Although it seems to lack the slight afterglow that codeine seems to produce.hmmm.
A few years ago I was doing otc CWE's every other day, I must know where every pharmacy is in south birmingham! In the end I needed two packs to get a proper dunt.
Over this time I found a great variety in the ease of separation by brand. Generally try to avoid the non-branded/generic variety that you find in independent pharmacies. Sainsbury's own brand was a waste of time as were Boot's Capsules, although boots tablets were one of the best!? For codeine nothing beats lloyds own brand, and for DHC it's paramol (bit pricey tho!).
I found you could increase the extraction efficiency by using a 2 filter method. Using some tight woven cloth like material for the first run captures almost all of the filler/gunk and allows you to squeeze the liquid though. If you're a good brand you should be able to push practically all the water though, leaving an almost dry powdery substance behind. Difficult brands seem to trap a lot of liquid in the binders/fillers that can't be removed.
This 2 filter method completely avoids clogging of the coffee filter while still capturing rouge paracetamol and ime produces significantly more opiate containing liquid at the end. It doesn't take much longer either because the coffee filter stage is very quick with the majority of fillers and binders already removed
Paramol always produced a slightly cloudy result, which is normal. Its not paracetamol, just some filler small enough to get though the filter. DON'T apply this logic to other brands though. Its just a fairly well known fact that paramol does this
Was always to scared to ask for linctus or morphine tinctures. Did get some Collis Browns mixture a couple of times off t'internet tho. I think it was 20mg morphine per bottle, so I needed a couple.
So much easier that CWE, it's not even a syrup, rather water consistency, so I diluted the two bottles with water in a pint glass and it went down like a charm.
In case anyone was wondering I recently had a liver function test and an actual scan of my liver. They both came back completely normal.
Which leads me to believe CWE is completely safe if done correctly, but if you have any doubts about the procedure or the final product discard it and put it down to experience, tis not worth the risk.
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Bloody hell, sorry, I didn't set out to write a mostly off topic mini essay!