morphine analogue opiate based antitussive cough medication which in many regions largely replaced codeine linctus as it has a much lower potential for dependence
helps suppress non-productive coughs
has a mild sedative effect, but has little or no analgesic effects
withdrawn by TGA in Australia in 2023 as increases risk of anaphylaxis during general anaesthesia by 300x for the next few years after dosing
has been demonstrated to be a potent IgE-sensitizing agent, sensitizing individuals to epitopes common to neuro-muscular blockers
this is due to production of anti-suxamethonium antibodies which gradually fall over a few years
this was discovered when it was noted that Norway and Sweden were found to have tenfold differences of surgical anaphylaxis deaths and pholcodine was not available in Sweden but it was in Norway
Norway banned it in 2007, EU market withdrew it in 2022, Australia in Feb 2023, UK in March 2023
in USA is not used as it is classed a Schedule I drug