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Respiratory Full Study and Histamine Challenge Test.

Hello, I have received a letter from my hospital and have been told that I have to go for a Respiratory Full Study and a Histamine Challenge Test. I was just wondering what these tests are and what should I expect when I get there. I've tried looking online but there is no information. Thank you

4 Replies

Hi Jemm_beth99

A respiratory full study involves breathing in different concentrations of histamine in a very controlled setting over a period of time as well as doing your breathing test after each concentration to see how your lungs respond to the histamine, it might take up to 90 minutes.. The tests can stop at any point in time depending on depending on how your lungs react. Your breathing test has to drop by 20% for it is be positive.

Hope that helps,



Thank you very much.



Hello, I have to go to the hospital this Friday for a Methacholine Challenge Test. Is this similar to the one mentioned by Jemma? The thing that worries me most is that I've been told not to use my inhalers for 12 hours before the test, and also my GP said I mustn't be taking prednisolone when I go. I have gradually reduced the pred so that today is my first day without any, and usually I start to cough and wheeze after about 3 days without. I am OK at the moment but my PF is down to 180 and I'm worried that by Friday morning I'll be in no state to take any test at all.


Hi there , Dita, gave you a great reply. I would only add that you should get instructions from the hospital about what medications you have to stop for between 24/48hours before the test. This is the gold standard test for reversibility in asthma, however I have had it twice, and it is not the greatest experience. So don't plan to have a super busy day afterwards. Good luck.

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