The invention provides stable S-nitrosothiol, such as S-nitrosoglutathione, formulations for long term storage and in vivo delivery of S-nitrosothiols. The invention provides stable aerosol formulations comprising S-nitrosothiol, such as S-nitrosoglutathione, and methods of treating patients in need of S-nitrosothiol, such as S-nitrosoglutathione, and/or nitric oxide treatment.