Dr. Zachary Clyde Terwilliger, MD

Dr. Terwilliger practices at Halifax Health Medical Center of Daytona Beach in Daytona Beach, Florida, part of Halifax Health District.

Dr. Terwilliger's NPI, 1881058881, was assigned on April 6, 2016. Dr. Terwilliger graduated from American University of the Caribbean School of Medicine in 2016. Dr. Terwilliger holds Florida license ME138339.

Dr. Terwilliger's primary practice is Halifax Health Medical Center of Daytona Beach, at 303 N Clyde Morris Blvd, Daytona Beach, FL 32114 in Volusia County. The practice phone is (386) 254-4000.

Dr. Terwilliger's primary practice is Halifax Health Medical Center of Daytona Beach in Daytona Beach, Florida, part of Halifax Health District. Dr. Terwilliger is also affiliated with Orlando Health Sebastian River Hospital. The medical group on file is Emergency Medicine Services of Florida. Dmand AI also links Dr. Terwilliger to 3 more medical groups, 1 behavioral health center and 1 group practice or clinic, each named with a free account.

Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Terwilliger practices, 4 sites in all. Vendor and product names are available with a free account.

Emergency medicine is Dr. Terwilliger's primary specialty in the NPI Registry, under taxonomy code 207P00000X. Dr. Terwilliger is board certified in emergency medicine by the American Board of Emergency Medicine. Dr. Terwilliger is licensed in Florida.

CMS data shows 424 Medicare services from Dr. Terwilliger across 6 procedure codes in 2024, for 372 Medicare patients. Medicare paid $45,574 for them. Every service was in a facility, such as a hospital, rather than an office.

CMS counts 372 Medicare patients who saw Dr. Terwilliger in 2024. The largest group is 75 to 84, with 119 patients. 75% of them have high blood pressure, and 75% have high cholesterol. 30% are also on Medicaid. Their average risk score is 2.43, where 1.00 is the Medicare average, so they are sicker than most Medicare patients.

Across all payers, Dmand AI patient panel data puts Dr. Terwilliger's median patient age at 57, with 55% women.

In 2024, Dr. Terwilliger wrote 292 Medicare Part D claims for 190 patients. 92% of them were for generic drugs. CMS names the drug for 122 of them, across 6 drugs with 11 or more claims each, at $882 in total drug cost. In 2023, CMS named 48 claims across 3 drugs.

Dr. Terwilliger accepts Medicare assignment, so Medicare's approved amount is taken as full payment.

CMS Open Payments shows 31 general payments to Dr. Terwilliger from 8 drug and device companies from 2020 to 2025. Food and beverage make up the largest share, 100% of the total. Abbvie Inc. paid the most, $298.

Dmand AI lists 3 awards for Dr. Terwilliger, most recently ACEP National Councilor, Scientific Assembly in 2024. Dr. Terwilliger serves on CME Committee, Medical Executive Committee UF Health Halifax Deltona and Halifax Health Blood Utilization Committee.

Dr. Terwilliger graduated from American University of the Caribbean School of Medicine in 2016. Dr. Terwilliger is a member of ACEP and Florida College of Emergency Physicians.

Dr. Terwilliger is in network with 5 carriers, including Excellus BlueCross BlueShield, United Healthcare and CMS Medicare. Medicare plans come from the most carriers, 3. Check the plan with the practice before a visit.