GPT and Muscle spasm: The ADRs most frequently observed in the clinical trials cited in the new-drug application of eplerenone in Japan included headache (6.1%), dizziness (2.6%), nausea (1.9%), hyperkalemia (1.7%), fatigue (1.6%), increased alanine aminotransferase (1.4%), increased gamma-glutamyl transferase (1.3%), indigestion (1.2%), increased aspartate aminotransferase (1.2%), muscle spasms (1.0%), and hyperuricemia (1.0%).