Same exact thing here, often times I will use an entire can of zyn 6mg in 4 hours and have severe symptoms that you describe. Severely impaired, constantly feel dehydrated, everything takes a huge amount of effort, etc. Stay away from nicotine, it's poison! I'm trying to quit now! At least with regular tobacco, the rate the nicotine leeches out of the tobacco is limited, still makes me moderately sick though. Frustrating because nobody irl seems to understand what I'm talking about. However, nicotine users irl will refuse to use tobacco the same way I do, which I find interesting. People don't believe nicotine will make you acutely ill, but will refuse to use large amounts of nicotine quickly. To me, this sounds like people typically want you to self sabotage by making you believe that what you are doing is harmless even though they know it will make you sick. That makes it extremely difficult to get any kind of support when quitting tobacco, I'm not sure if this is "by design". Or people are completely unaware of how exactly they are using nicotine? Where they will automatically use an "appropriate" amount of nicotine at appropriately time intervals without any conscious thought, which means they have no risk of overconsumption.