What does an allergist do?
An allergist is a doctor who diagnoses and treats allergies and asthma. They find out what triggers your reactions and plan how to manage them.
Last updated November 11, 2026
When people see one
- Hay fever or sinus symptoms that medicine does not control
- A reaction to food, an insect sting, or a medicine
- Asthma that keeps flaring up
- Hives or eczema with no clear cause
How it differs
Ear, nose and throat doctor (ENT): An ENT treats the ears, nose, and throat, including some allergy-related sinus problems. An allergist tests for triggers and treats the immune reaction behind them.
On 2027 Colorado plans
Do you need a referral? On some plans. 37 of the 148 2027 plans need a referral from your primary care provider to see a specialist: Kaiser Permanente's 29 plans (you may self-refer to certain specialists) and Denver Health (Elevate)'s 8 plans (self-referral allowed for OB-GYN and outpatient mental health care). The other 111 don't, according to each plan's 2027 summary of benefits. Confirm in the plan's summary of benefits.
What a visit costs (the plan's filed "Specialist Visit" benefit, in network, before any extra savings on silver plans):
- Bronze: $100 to $140 a visit on 10 of 56 plans; on the other 46, you pay toward your deductible or a share of the bill.
- Silver: $50 to $90 a visit on 44 of 58 plans; on the other 14, you pay toward your deductible or a share of the bill.
- Gold: $50 to $90 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 120 allergists at 82 Colorado locations.
- El Paso County: 11 locations
- Denver County: 10 locations
- Arapahoe County: 9 locations
- Jefferson County: 9 locations
- Douglas County: 8 locations
- Boulder County: 7 locations
Counties with the fewest: Yuma (1), Weld (1), Montrose (1), Garfield (1), Alamosa (1). 46 counties have none.
Questions to ask the office
- Do I need a referral from my primary care doctor?
- Which 2027 plans and network names do you take?
- How long is the wait for a new patient?
- Is allergy testing done at this office, or somewhere else?