I have no experience with asthma so can not help you with any personal testimony.

But I can steer you to some doctors that I think highly of their advice. Not that I agree with all of it 100% of the time, but their ideas are worth considering. Kind of like advice from a best friend. You don't do every thing they say, but you respect them enough to hear them out because you value their opinion.

I personally would probably not go directly to carnivore, but it certainly is the ultimate elimination diet. I think you would find the transition easier to go to a ketogenic diet then to carnivore if you did not find the relief you wanted from keto. But having said that, some people with chronic conditions may find the transition to carnivore less stressful than the condition they suffer from so find it quite doable. Your call.

These are just some You Tube searches that might have some useful information.

https://www.youtube.com/results?search_query=dr+ken+berry+asthma

Dr Berry is a big proponent of keto that has transitioned to primarily carnivore in his own personal journey.

https://www.youtube.com/results?search_query=dr+shawn+baker+asthma   nothing specifically comes up for asthma with Baker but I know he has covered it many times in his talks. He is a proponent of carnivore.

My wife and I started our keto almost two years ago and have slowly dropped most of the vegetables. There are still a few things we like and eat that are non-meat and if we go out to eat and with only limited valid choices on the menu sides we will eat a salad. But I would say that 90% of what we eat now is meat, my wife more so than me. She feels the best when she avoids the veggies. I can take them or leave them, doesn't seem to make much difference other than they give me gas. But unlike my wife, I just look at that as a sporting event.

The great thing about it is that it costs very little to try keto or carnivore. Maybe a little more in groceries but if a person cuts out some junk food probably not even increased cost. Certainly a lot cheaper than most drugs. If it works, great. If not all that is lost is not eating some foods a person enjoys. I have found other foods I enjoy now that I did not in the past. Some I would not have touched with a ten foot pole.

I found relief from a lot of health issues I was having anywhere from the first week to the first month. If it is going to make a difference I think you will at least start to feel it within a couple weeks. It could take months or years to gain all the benefits, hard to say. But if you do not feel at least improvement within the first two or three weeks, I would think it is not going to help much. Just my opinion.

John