Jean Baptiste Bouillaud (1790-1881) was a french physician. He received his medical doctorate in 1823 and later was a professor at the Charit矇 in Paris. In 1862 Bouillaud was elected president of the Acad矇mie de M矇decine, and in 1868 he became a member of the Acad矇mie des sciences. Bouillaud performed research of many medical diseases and conditions, including cancer, cholera, heart disease and encephalitis. He is remembered for providing a correlation between rheumatism and heart disease, and French medical dictionaries still refer to acute rheumatoid endocarditis as "Bouillaud's disease". He described this condition in the treatise Trait矇 clinique des maladies du coeur. Bouillaud was an early practitioner of the drug digitalis for treatment of heart ailments. He referred to digitalis as the "opium of the heart". Along with cardiologist Pierre Potain (1825-1901) he performed studies of "heart sounds" involving the differentiation between normal and abnormal heart rhythms.