Lottie Cornella Isbell Blake, M.D., (10 June 1876 – 16 November 1976) was an American physician, medical missionary, and educator.

During her life, Dr. Lottie Blake became licensed to practice medicine in Ohio, Tennessee, Alabama, Panama, West Virginia and Pennsylvania.

The Isbell children were raised as Baptists for much of their youth but when Lottie was twenty years old she, her mother, and her sister Mamie converted to become members of the Seventh-day Adventist church.

Dr. John Harvey Kellogg, director of the Battle Creek Sanitarium, with whom she lived and worked under became a mentor for Blake during her years as a nurse.

She graduated from the American Medical Missionary College in 1902 at 26 years old, becoming the first black Seventh Day Adventist to become a physician.

She worked as the director of the Rock City Sanitarium in Nashville, Tennessee and a practicing physician in Birmingham, Alabama.

In May 1916, General Conference leaders sympathized with their situation and gave them $200 for their church and $150 grant-in-aid to David for his mission work in Cape Haitien.

Lottie Blake sent her children to live with family in Columbus, Ohio while she went to practice in Charleston in 1920 and stayed for five years.

In her retirement years, she continued to give Bible studies and teaching religious literature to those who sought to learn from her.

She left behind a legacy of high faith, power in education, and a determination to serve and treat the African American community.