A strict low-biogenic amine diet should be observed as a matter of principle, followed by a re-introduction phase, with the establishment of a permanent diet at a later stage.
It is very important to coordinate this precisely with your doctor and your registered dietician!
An enzyme product containing Diamine Oxidase (DAO) breaks down ingested histamine. DAO is available worldwide under the brand name "DAOsin" and can be bought online. It was acknowledged by the U.S. Food and Drug Administration in 2008 and is also available in the U.S.
Some sources recommend taking supplements of Vitamin B6 and Vitamin C.
It is recommended that you carry an emergency pack (speak with your doctor about this!) with you at all times. The pack should include some form of anti-histamine and maybe an asthma pocket inhaler (if you had asthmatic symptoms previously).
The emergency pack is not a replacement for the diet!
Some drugs enhance the intolerance symptoms! If you are already taking medication for any other health reason, ask your doctor about their effect on the histamine intolerance! There are a lot of substances used in different drugs that have a negative effect on the DAO enzyme. So do not change your medication before you have talked to your doctor, as otherwise you may seriously harm your health.
Jarisch, R. "Histaminunverträglichkeit", Thieme Verlag TB 2. Auflage
Buchart, K. "Gut leben mit Nahrungsmittelallergien", Löwenzahn Verlag, 2008
Laura Maintz, Natalija Novak (2007)American Journal of Clinical Nutrition85 (5) p. 1185-1196
Masterman, G. "What HIT me? Living with Histamine Intolerance", 2010; createspace; www.histamineintolerance.org.uk