Dr. Mary Louise Lenahan is a Buffalo native and third generation doctor. She graduated from medical school in 1979, and completed her residency in dermatology at SUNY Buffalo. In 1985, Dr. Lenahan opened her private practice in Buffalo and has been treating patients with care for the past 35 years and counting.Cosmetic‧Contact‧Laser‧Lenahan Dermatology‧Welcome‧Terms & Conditions.