I have tried them in inhalers and levalbuterol in a nebulizer and they make me jittery .I took levalbuterol yesturday morning at about 11:30 am in my nebulizer and it did not make me jittery .Then last night at 10 to 12 am I took levalbuterol again in my nebulizer .At first I felt ok but then about 3:30 or 4 am it started to make me jittery and now its just after 7 am and I sm still somewhat jittery but maybe not as much as earlier .I was not able to get to sleep though and I have been up all night.