Dora Thomas Head, 85, who cared for patients from St. Elizabeth Hospital at her home in Washington for more than 20 years, died Tuesday at Providence Hospital. She had a heart ailment.

Mrs. Head was born in Madison, Va., and attended schools there. She moved to Washington while still a young woman and for many years worked as a nurse maid and housekeeper for families in the Washington area.

In the mid-1950s, she received a license from the old D.C. welfare department, now the Department of Human Resources, to be a director of a home for patients from St. Elizabeths. She continued to work in this capacity until shortly before her death, caring for patients who no longer needed hospitalization but still required a lesser degree of care.

Mrs. Head was a member of the Northeast Holy Trinity Church in Washington for 50 years and recently was honored as the only member of the congregation in her 80s.

Her husband, Major Head, died in 1937. A daughter, Mabel Head, died in 1922. Another daughter, Sadie Ballard Williamson, died in 1973.

Survivors include a son, Linwood Head, of Washington, 13 grandchildren, and six great-grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the American Heart Association.