I was diagnosed with severe allergies in 1992. I had had many symptoms since age 8 that point to mcas. Unfortunately, I did not have diagnosis until 2021. My allergists, I had 2 at time, both tried to capture my tryptase levels during flares but mine rise/drop very quickly. Most drs say get tryptase level within 2 hours of flare up. I have to be tested within 10 minutes or it will comeback within normal limits. Was fortunate to have flare up while in hospital and they could draw blood immediately. My tryptase was over 18. Within 10 minutes, it was back to 10. It took many years for my diagnosis. Was sent to many specialists. Had wrong diagnosis for years. (Fibro, seasonal allergies, lupus, irritable bowel, migraines, tmj, meningitis, plus more). None were quite right as reason for symptoms but the drs I was dealing with were not familiar with mast cell issues so I had multiple diagnosis for the symptoms I have.