Knott Street Dermatology offers a wide array of dermatological treatments for patients with various skin conditions. One of these is Excimer (Xtrac®), which can address psoriasis and vitiligo.

Psoriasis is a skin disease causing red, itchy scaly patches, usually on the knees, elbows, torso and scalp. Vitiligo is a condition where the skin loses pigment, resulting in discolored patches in areas of the body.

Excimer (Xtrac®) is a form of laser treatment that utilizes ultraviolet (UVB) light to treat various skin diseases, including psoriasis and vitiligo. Exposure to beneficial high energy UV light is applied to the affected areas for varying lengths of time, while the UV rays that cause burning are eliminated. Total number of treatments and clearing time will vary by patient and condition. Though not a cure, this treatment can effectively control and improve these conditions. Since its invention in 1970, patients have used this treatment successfully and are often able to maintain clearance of improved skin for extended periods of time.

To learn more about treatments for skin conditions, contact Knott Street Dermatology for immediate consultation, or send in your queries through our website. Reach out to us today for a scheduled appointment to learn more. Knott Street Dermatology treats patients in and around Portland including Happy Valley, Clackamas, Gladstone, Damascus, Gresham, and Fairview.



Checkout our before and after gallery where we feature a few our recent patients. 






Our team is made up of experienced professionals
excited to help and provide personalized care just for you.

Alicia McCarthy, ND

Dr. Alicia McCarthy earned her Bachelor of Science in Kinesiology degree from California State University of Fullerton in 2008 and her Naturopathic Medical degree in 2017 from National University of Natural Medicine in Portland, OR. The twelve years Dr. McCarthy spent working in emergency medicine as an EMT set the foundation for the provider she is today. She now specializes in aesthetic medicine, dedicating her continuing education and practice to staying current on the latest techniques and products. Dr. McCarthy believes in aging gracefully. She takes the time to sit down with each patient and find out what this means for them.

Prior to joining Knott Street Dermatology, Dr. McCarthy had her own practice in Lake Oswego focused on aesthetic medicine, hormone balancing, thyroid conditions, and IV medicine.

Originally from Southern California, Dr. McCarthy has lived in Portland for the last eleven years. When she is not working Dr. McCarthy stays busy with her two young kids, husky pup, and husband. They enjoy spending time outside, camping, swimming, and playing at the park.

Olivia | Knott Street Dermatology | Skin Care Center | Portland Oregon

Olivia Gill LE,CAE

Olivia graduated from Spectrum Advanced Aesthetics in 2015 and has been working full time as a Certified Advanced Esthetician and Laser Safety Officer for the last 6 years. Olivia’s favorite part about her job is helping her patients feel more confident in their own skin. She takes pride in tailoring each skin care regimen and treatment plan to fit everyone’s lifestyle and budget. When she’s not pampering patients, she enjoys camping, traveling, and quality time spent with her family, husband, and Corgi puppy- Ginger!

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If you have any questions, concerns, or would like to schedule an appointment please let us know. 



FIVE STARS Rating | Knott Street Dermatology | Best Dermatologist | Portland OR

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