Yes, if too strong they can make you a bit rough.
I was quite ill after putting 2 in at once after 6 pints of some 8% stout...
Yup. It was obviously the snus

Something similar happened to me with a "dodgy kebab" one night after an all day sesh at the local highland games....



I was doing some work for a guy from London who smoked a pipe. His tobacco of choice was called Sweet Peach and the aroma was so pleasant, I asked him where he bought it as I wanted to try smoking it in my roll-ups. He ordered it from a tobacconist in London and got some for me on his next order. It smelt wonderful but didn't smoke too well in rollies!!