My doctor put me on Albuterol (Proventil) when I was originally diagnosed with asthma (age 22). The first time I used the inhaler was my last. I took one puff, and in about three minutes, I felt awful. I began to shake uncontrollably (almost seizure-like in intensity). My heart rate went well over 180 bpm. I had terrible crushing chest pains. And I became extremely confused. My mom kept asking me if I was alright and if I thought I needed to go to the ER. I kept telling her I didn't know, because I really had no clue. I didn't even know where I was, even though I was lying on the couch in my livingroom. After about 20 minutes, everything subsided, except for some slight residual trembling, and I fell asleep. Needless to say, I have never taken this medicine again. (Although, as my mom pointed out, it DID stop my asthma attack.) I now take Primatine Mist, which is epinephrine and sold OTC. It doesn't work quite as well at stopping my asthma attacks, but it does provide relief without all the horrible side effects.