A composition containing levosimendan, one or more solubilizing and/or stabilizing agents, and one or more additional pharmaceutically acceptable additives. The one or more solubilizing and/or stabilizing agents may be a cyclodextrin or a cyclodextrin derivative. The cyclodextrin derivative may be a derivative of an alpha-cyclodextrin, or beta-cyclodextrin, or a gamma-cyclodextrin. The cyclodextrin derivative may contain a butyl ether spacer group, an alkyl ether space group, or both. The one or more additional pharmaceutically acceptable additives may be a non-citrate buffer. The composition may be used in a method of treating a health condition, such as heart failure, pulmonary hypertension, chronic kidney disease, amyotrophic lateral sclerosis, stroke, in advance of a planned cardiac surgery, or other health conditions for which a minimally invasive or repeated administration of levosimendan may be beneficial. The composition may be administered subcutaneously.