Sounds like you may have become sensitized to the menthol, in which case it will probably never agree with you again, much the same way bakers can become sensitized to flour of plasterers to cement etc, even after years of previously using these compounds with no ill effects. I suggest you leave it for a week or so before trying it again and see if the menthol still caused irritation.
I had a similar issue with mentholated snuff. I gave it a few weeks rest and I was back to normal. I don’t use mentholated snuff as much as a precaution. Mind you it was when I only had about 3-5 different snuffs and the mentholated was my favorite so I was taking that the most by far. Now that I have a bigger collection of better snuffs, it isn’t as prominent in my rotation.
I had the exact same issue. My snuff o choice for over a year was Bernard fichtenadel, one day, bam sneezing and congestion. Took a few days off - same thing. Now 6 months down the road I can have a little bit at a time with no ill effects. But if I have just a bit too much - sneezing and congestion. I am hoping it will slowly go away
Having given the Mcc a rest for a few days and using F&T Bordeaux I had no issues. I will give it a few more days and try some of the beloved Original & Genuine!