I managed to take down my hay fever this spring. In my case it can lead to sneeze attack, deoxygenation, and hyperventilation, so I went at it with all I had. What I did:
(1) Eating a quite strict ketogenic diet, and only organic foods
(2) taking regular DMSO (1/2 tsp of 99% liquid, in water, every seven days)
(3) significant doses of iodine protocol (around 8 drops of what I recall is 2.5% Lugol's), with the B vitamin combo, Selenium, and salt water
(4) Magnesium Bisglycinate every night
(5) one dropper full of Goldenrod tincture every day
(6) when I was at work and felt the red eyes, itchy nose, sneezing, I would take 6000 mg Vit C. If symptoms continued after an hour or so, I would take another dose of 6000 mg, and continued doing so until symptoms subsided. Some days around 24 000 mg Vit C was required.
(7) salt water and sodium bicarbonate first thing every morning
(8) 3 mg melatonin every night
(9) kept on smokin'
Results - I had extremely reduced irritation in comparison to previous years. I was blown away. I could actually breathe in a field full of flowering grasses! There was some irritation, but overall, it was incredible!
Side effects - I had significant bowel intolerance, difficulty passing stools, and liquid stools. This is probably a combination of (1) my recent keto-adaptation, plus (2) high Vit C intake. My guess is that the bowel troubles were mostly based on the strictness of my keto diet, but probably exacerbated by the high Vit C intake. When I first went keto is when I first noticed the bowel issues. And since the spring, I've included some carbs back into my diet. This has lead to a much more normal bowel performance. Now I know that my body just doesn't like that.