Most common side affects associated with this medication include coughing, nausea, headache, and shaking. More serious side affects include chest pain, increased heartbeat, and muscle cramp. Talk to a local doctor immediately if these side effects are experienced after you buy Proventil. Serious allergic reactions are possible and can be followed by swelling in the face, tongue or throat. Itching, rash, and increased difficulty with breathing were also reported. There are a number of possible side effects with that you should report immediately to a local physician, including, but not limited to worsening breathing problems, irregular heart rhythm, very fast heart rate, high blood pressure. Less common side effects include hoarseness, vomiting, vertigo, insomnia, headache, unusual taste, dry or sore throat.