What does an internal medicine doctor do?
An internal medicine doctor, or internist, is a physician who cares for adults. Internists diagnose and treat many conditions and manage long-term illness.
Last updated November 11, 2026
Find internal medicine doctors near you
When people see one
- Yearly adult checkups
- Managing diabetes, heart disease, or high blood pressure
- Symptoms that need a workup
- A referral to a specialist
How it differs
Family medicine doctor: Internists see adults only. Family medicine doctors also see children and can care for a whole household.
Geriatrician: Many internists see older adults, but a geriatrician has extra training in the care of people who are usually 65 and older.
On 2027 Colorado plans
Do you need a referral? No. You don't need a referral for primary care.
What a visit costs (the plan's filed "Primary Care Visit to Treat an Injury or Illness" benefit, in network, before any extra savings on silver plans):
- Bronze: $25 to $50 a visit on 23 of 56 plans; on the other 33, you pay toward your deductible or a share of the bill.
- Silver: $0 to $40 a visit on 53 of 58 plans; on the other 5, you pay toward your deductible or a share of the bill.
- Gold: $0 to $30 a visit on 26 of 30 plans; on the other 4, you pay toward your deductible or a share of the bill.
In-network care costs less. Out-of-network visits on an HMO or EPO usually aren't covered except in an emergency.
In Colorado
Public records list 2,979 internal medicine doctors at 893 Colorado locations.
- Denver County: 143 locations
- Arapahoe County: 111 locations
- El Paso County: 93 locations
- Jefferson County: 89 locations
- Boulder County: 79 locations
- Douglas County: 65 locations
Counties with the fewest: San Juan (1), Prowers (1), Moffat (1), Huerfano (1), Custer (1). 21 counties have none.
Questions to ask the office
- Are you taking new patients?
- Which 2027 plans do you take? Ask for the plan's network name, not only the insurance company.
- Do you manage ongoing conditions like diabetes in the office?
- Which hospital do you send patients to?