Opioids effervescent co-codamol uk

[kaosisallwesee]

I've read/been told conflicting info regarding performing a CWE on these. Some say the paracetamol is in a more soluble form, I find this hard to believe as I cant find a shed of evidence that states this is the case. I've studied pharmaceutical science at degree level and when covering effervescent solid dosage forms we were told they work by forming a suspension of paracetamol rather than a solution. The reaction between citric acid and a weak base produces effervescence, which keeps the slightly soluble paracetamol in suspension. So why are they reported to be unsuitable for CWE?

 

[Wilson Wilson]

The preparation doesn't change the simple fact that codeine is water soluble and paracetamol is not. That's just basic chemistry that applies to any form of those drugs.

It is however entirely possible that the fillers added to effervescent tablets complicate the process but in theory you should be able to just leave them in water as usual then filter out the codeine after. Paracetamol is not water soluble. Codeine is. That doesn't change.

The basic principles of chemistry behind CWE remain. I've not attempted a CWE with these tablets myself so if you are concerned, assuming these are just the usual 8/500 ones you can get OTC, why not just get a box of normal 8/500 cocodamol tablets from any pharmacy instead?

If they're 30/500 and you don't wanna risk anything, you should be alright to just stick to the safe level of paracetamol (4000mg a day). This isn't a good idea in the long-term, but for short-term it should be fine unless you have preexisting liver issues.

If you're really really worried about the paracetamol and just want clean codeine, order a bottle of codeine linctus tbh.

 

[kaosisallwesee]

For anyone interested, I've come up with an a few reasons why you cant use effervescent tablet. I can't find much solid info on this first point, but it would seem that the combination of paracetamol and certain excipients results in a more soluble form. Either due to CO2 produced by the reaction between sodium bi/carbonate and citric acid, possibly forming a carbonate salt or involving citric acid and the citrate.
The volume of water needed would be rather large, meaning even if the paracetamol retained it usual dissolution characteristics, there'd be a few grams in solution.
And finally the amount of sweetener in the resulting solution would also be pretty big, and most likely unbearable to consume.

 

[Wilson Wilson]

Interesting so it is basically down to the fillers complicating matters.

Best to just use regular co-codamol tablets it seems, especially if we're talking about the 8/500 OTC strength. Cheap as chips and available at any pharmacy. No need to dick about with these.