Hi all - I have been a heroin user almost 20 years, & for most of them also on a moderate level of methadone. Around a year ago I increased my 'done to 100mg for around 6 months, then back down to 80. Around the same time I started getting quite sick (severe headache/migraine, nausea etc) after using. This starts after an hour or so and can last up to a day. Haven't changed the amount I use, & the source doesn't make a difference (others using the same are fine). I don't have Hep C but I do drink a lot. My GP said it was reasonably common in long term users or those on higher methadone, but I've never heard that, & he didn't explain why. Has anyone else found this happening? It's not necessarily a bad thing (I've pretty much stopped using altogether), but I just don't understand it.