This invention relates to ready-to-use and safe solution compositions of glucagon suitable for administration by manual injection or by an insulin pump or other injection device to treat hypoglycemia. Said compositions comprise glucagon, an acid, anti-gelling polyol, a stabilizing-salt, viscosity reducer and an antioxidant, have a final pH between about 2 and 5, and is gel-free, chemically-stable, and pump-able.