Dr. Viehman was born and raised in Wilmington, Delaware. He attended and graduated magna cum laude from the University of Delaware. Dr. Viehman attended medical school at Jefferson Medical College in Philadelphia, Pennsylvania, and graduated number one in his class. He completed an Internship in Internal Medicine at the Hospital of the University of Pennsylvania in Philadelphia, and a dermatology residency at Duke University Medical Center, where he was chief resident. Dr. Viehman completed his fellowship in Mohs Micrographic Surgery and Dermatologic Surgery with Dr. Clark at the Dermatologic Surgery Unit & Cosmetic Laser Center at Duke University Medical Center. He was Assistant Director from 1997–98. Dr. Viehman was then a cofounder and medical director at the Cary Skin Center in Cary, North Carolina, from 1998–2008.

He has lectured nationally on dermatologic surgery, authored several published articles, and written a book on dermatologic differential diagnosis. Dr. Viehman is double Board certified in Dermatology and in Mohs Micrographic Dermatologic Surgery. As of 2019, Dr. Viehman has performed more than 35,000 Mohs procedures.

Dr. Viehman lives with his wife and three children along with a border collie named Pepper. Dr. Viehman completed his masters degree in Theology from Liberty University Baptist Theological Seminary with High Distinction in 2015. Dr. Viehman is also an author of two Christian books: “The God Diagnosis” and “The Abundant Life.” He also is president of a non-profit organization: Everlasting Strength Ministries.