I didn't answer this sooner because by the time I first read it... It was already too late to give any truly constructive advice, aside from... Don't let your dog get into the medicine cabinet!
However, for future reference, if anyone should stumble across this post seeking an answer, I will give my thoughts.
If a dog eats anything potentially dangerous, that is not caustic (acids, cleansers, bleach, petroleum products.. Anything that's going to cause more damage to the lungs or esophagus coming back up than it will traveling on through)... You should induce vomiting as soon as possible. Give the dog 1-3 tsp. Of hydrogen peroxide every 10 min. Until the dog vomits... It usually only takes minutes before fido completely empties the contents of his stomach, and tries for more... It's pitiful.. But it's very temporary, and will save you and him a lot of grief in the long run.. After his stomach settles down a bit, offer him a little yogurt or some rice boiled in broth to help sooth his pipes. And tell him what a good dog he's been.
