As a component of Dr. Bruce Patterson's treatment regimen (his working theory is vascular inflammation is the root cause of all of our LC symptoms) I am on a low histamine diet and taking DAO (over the counter) and a couple of complimentary prescriptions (famotidine, cetirizine). Histamines cause inflammation, thus this as part of his approach. As an aside I am not permitted to SCUBA Dive because the compression and decompression is an inflammatory activity. Exercise to the point of sweating is an inflammatory activity. I fave found guidance and science very lacking about histamine, but did find an app for my phone that keeps me in bounds ("Intolerances" provided by a German company). My approach is DAO and the prescriptions plus not consuming things that I refer to as "histamine explosions". Things like red wine, tomatoes, bacon, whisky, anything cured, aged, fermented. Per the app I stay under 4mg of histamine per day which is considered average histamine consumption. There are foods and drinks that add histamine, and that release histamine. Many things to navigate but with the help of the app I believe I am doing that successfully.