On Canada Day, the Museum of Health Care unveiled a new exhibit entitled “A Stubborn Illness” about the health of Sir John A. Macdonald and his family. When I first toured the gallery I was struck by the intriguing medicine prescribed to Sir John A. Macdonald’s first wife, Isabella Clark. Visitors seemed to share my sentiment and several have inquired why laudanum is no longer a popular treatment. Further investigation of laudanum and Isabella’s relationship with it reveals that though the drug provided pain relief, its side effects and risks far outweighed its benefits.