It is generally well-tolerated, though mild side effects such as headache, fatigue, or gastrointestinal discomfort can occur
Frings D, Albery IP, Moss AC, Brunger H, Burghela M, White S, and Wood KV (2020) Comparison of Allen Carrs Easyway programme with a specialist behavioural and pharmacological smoking cessation support service: A randomised controlled trial
Chewing tobacco is typically done by placing a pinch of tobacco in the mouth between the teeth and lip or cheek and leaving it there
I always go in the upper lip (since I'm a snuser), for less salivary gland contact and less reason to spit
If the swallowed object is smooth and relatively small, most of the time it can pass through your dogs system