CalmSupport does NOT contain Slippery Elm Bark.
Slippery elm has no serious side effects. Because it coats the digestive tract, it may slow down the absorption of other drugs or herbs. You should take slippery elm bark 2 hours before or after other herbs or medications you may be taking.
Source: http://www.umm.edu/altmed/articles/slippery-elm-000274.htm