Dr. Christopher John Zajac, MD. Dr. Christopher John Zajac, MD. Languages: English. Phone: (410) 256-9340. Fax: (410) 529-9465. Contact this Provider: (410) 256-9340. ... Find a Doctor Careers Patient Portal Make a Donation Billing & Insurance Classes & Events Contact Us Newsroom Live Well & Healthy Blog MedStar Health DocTalk Podcast ....