after doing some study on this theres no answers but many people do suffer from the problem. It seems most likely to be dirty lines. As I said the beer tasted good. I remember ten years ago draft beer in walking street was undrinkable, and if I was with a lady she would tip it down the toilet to stop them reusing it. i have also had bottled beer in thailand that was undrinkable, checking the date on it it was usually only a month or so old but that seemed to be enough time for it to go off. But this beer tasted good. another possibility is tyramine. in any case there are people all over the world that cant drink draft beer but have no problem with canned beer. as its worldwide I doubt its formaldehyde. Its surprising that the beer companies haven't researched it, but there you go, and never again will I drink draft beer

thought that was the end of that but theres a little more to the story. was in the same place tonight, drinking a mango shake, and theres two middle aged japanese couples at the next table. the men are drinking the draft beer, which incidentally is anchor. as they are about to leave one of the men vomits and passes out and falls off his chair onto the floor smashing a few glasses and his head on the way. the staff were as helpful as they could be and he fortunately made a quick recovery and left, after which they explained that he passed out because japanese people cant drink beer. I told them that actually that beer had made me sick too. maybe the pipes needed cleaning. oh no, they said, only japanese people had a problem. I explained again that it made me sick too, perhaps it wasnt their fault but that there was a problem with that batch of beer. once again, nobody else has a problem, only japanese and I gave up at that stage. but anyway, that beer definitely has something wrong with it.