North Bay Allergy is a full service allergy and immunology practice with all Board Certified allergists. We have offices in both Napa and Sonoma.  We can diagnose and treat a full array of allergic conditions, including, allergic rhinitis, asthma, food allergies, chronic hives and swelling, eczema, drug allergy, insect allergy, contact dermatitis, chronic sinusitis and primary immune deficiencies.  Call to schedule an appointment.


New food allergy therapy now available.  Xolair injections approved for age 1 and up for people with food allergies to reduce allergic reactions, including anaphylaxis.  Available at North Bay Allergy & Asthma.  Call for more information and make an appointment.  You can also visit https://www.xolair.com/food-allergies.html for more information.

New peanut desensitization is available!  For more information, please visit Palforzia.com for product information.  To schedule a consultation to review the desensitization, please call us at 707-258-8100.

COVID-19 (Coronavirus) Advisory:

We are open for appointments, biologic, and allergy injections during our regular business hours.  We have become a hands-free office where you are not required to touch any surfaces.  In accordance with CDC, masks are now recommended, although not required for all patients.  All of our staff will continue to always wear masks for your safety.  We will still clean rooms in between patients, clean waiting room chairs and still have chairs available outside of our office for our patients.  We thank you for your cooperation during these trying times.

Testimonials about Dr. Ahn

Mrs. Smitherton

Dr. Ahn has been my allergist for at least four years now, and I continue to return to him because I trust him. He listens to me, and is open, friendly, relaxed and confident, and makes constant eye contact with me. He has offered me courses of treatment for my allergies that I chose not to take, because I chose to use acupuncture or a naturopath, and he was open and accepting of my choices without being pushy or denigrating natural medicine.

Mr. Johnston

I don’t know what I would have done had I not found Dr. Ahn. I have repeated swelling attacks of my lips and tongue and face and no other doctor knew what was going on. Dr. Ahn told me I had angioedema and started treatment for it. I can’t thank him enough.

 Appointment Hours

Monday - 9:00 am - 5:00 pm

Tuesday - 9:00 am - 5:00 pm

Wednesday - 9:00 am - 6:30 pm

Thursday - 9:00 am - 5:00 pm

Friday - 9:00 am - 12:00 pm


Napa Allergy Shot Hours

Monday - 9:00am - 12:00pm; 2:00pm - 6:00pm

Tuesday - 9:00 am - 12:00pm

Wednesday - 10:00 am - 12:00 pm; 2:00 pm - 6:30 pm

Thursday - 2:00 pm - 6:00 pm

Friday - 9:00 am - 12:00 pm


Sonoma Allergy Shot Hours

Monday - Closed

Tuesday - 2:00pm - 5:30pm

Wednesday - Closed

Thursday -  9:00 am-12:30 pm; 2:00 pm - 5:30 pm

Friday - Closed