Tinubu-Karch joined Sidra Medicine, an entity of the Qatar Foundation, in November 2022. In July 2024, the company signed an MoU with the Children’s National Hospital in Washington D.C. to establish a nursing partnership and engagement program. In May 2024, Sidra Medicine announced the upcoming establishment of Qatar's first pediatric hematopoietic stem cell transplant program in partnership with the Children's Hospital of Philadelphia. Tinubu-Karch is also the founder and CEO of 6M Geriatrics and Hospital Medicine. She was previously the clinical instructor at the University of Washington, School of Public Health.