Mehrdad Razavi, MD
Medical Director

Mehrdad Razavi, MD, is a sleep medicine specialist, visionary and Medical Director of Innovative Sleep Centers. He is board certified by the American Board of Psychiatry, Neurology, and Sleep Medicine. His 25 years of medical experience include 20 years in neurology and 15 years in sleep medicine. After finishing his medical training in Vienna, Austria, Dr. Razavi did his clinical training and was on medical faculty at the department of neurology of both the University of Iowa, Iowa City, IA, and Creighton University in Omaha, NE, before moving to private practice.   He enjoys providing comprehensive care to patients who suffer from a wide range of sleep disorders and improve their quality of life.  To raise awareness and educate the community, he was a featured national speaker and Medical Director of the Academy of Clinical Sleep Disorders Disciplines (ACSDD), a national inter-disciplinary sleep organization. He established his own independent practice, Innovative Sleep Centers (ISC) in 2010.

Board-Certified: American Board of Psychiatry and Neurology, Sleep Medicine
Fellowship: Behavioral Neurology, University of Iowa
Residency: Neurology, University of Iowa
Internship: Marshfield Clinic, University of Wisconsin
MD: University of Vienna School of Medicine, Vienna, Austria

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Chris Cheng, MD
Co-Medical Director

Dr. Cheng is triple-boarded in Neurology, Sleep Medicine, and Clinical Neurophysiology. Dr. Cheng graduated magna cum laude from UCLA, then received his MD with Latin honors from the State University of New York. Dr. Cheng then completed his Neurology Residency at NYU where he served as chief resident, and received the Resident Teacher of the Year award. Dr. Cheng completed a fellowship in Clinical Neurophysiology at UCLA Medical Center, and then completed a second fellowship in Sleep Medicine at Stanford Hospital & Clinics.

Dr. Cheng is devoted to excellent patient care, and sees the practice of neurology as an enormous privilege rather than something deserved. Having had the diversity of medical training along both coasts in some of the finest medical institutions, Dr. Cheng is capable of working with diverse patient backgrounds.  During his free time, Dr. Cheng loves to travel and hike with his wife who is a travel writer, run and play tennis, and spend time with his family.

Board-Certified: Neurology, Sleep Medicine, Clinical Neurophysiology
Fellowship-Training: Sleep Medicine, Stanford University, Palo Alto, CA
Fellowship-Training: Clinical & Intraoperative Neurophysiology, UCLA, Los Angeles, CA
Residency-Training: New York University School of Medicine, New York, NY
Medical School: State University of New York, Downstate College of Medicine, Brooklyn, NY.  

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Harrison Detroja, ARNP, FNP

Tumwater, WA

Prior to receiving his Nurse Practitioner degree from Eastern KY University, Harrison was educated and worked as a mechanical engineer.  He relocated to Washington and has been in healthcare since 2003 including his work as a primary care provider in Chehalis for 3 years prior to joining ISC.  He is passionate and persistent about improving all his patients' sleep health.

He enjoys the outdoors, hiking and spending time with family.

Erin McPeak, PA-C

Erin McPeak, PA-C

Chehalis, WA

As a Physician Assistant, Erin is committed to helping patients lead long, healthy, and active lives. She earned a master's degree in Physician Assistant studies from Butler University in Indiana and has been a Physician Assistant since 2011. She also has a bachelor’s degree in Exercise Science from Butler University. Erin is certified by the National Commission on Certification of Physician Assistants.

 In her free time, Erin is a competitive swimmer, runner, personal trainer, enjoys gardening, ceramics, floral design, and spending time with her dogs and family. Erin is also a NCAA Division II swimmer. She won the 200 yard butterfly for the Horizon League NCAA II Championships, and a United States Master's All-American Swimmer. Erin has prior experience in orthopaedic surgery, neurosurgery, and family practice and is glad to be a part of the Innovative Sleep Centers Team!


Phyllis Barks, PA

Aberdeen, WA

Phyllis Barks, MPH, PA graduated from the University of Florida Physician Assistant Program in 1980 and then obtained her Master of Public Health in Maternal & Child Health from the University of North Carolina - Chapel Hill in 1984. She has 20 years experience as faculty in several different Physician Assistant  Programs with the most recent one being the Oregon Health & Science University Physician Assistant Program in Portland OR for over 13 years. She also has 19 years of previous clinical experience in Women's Health and Family Practice. Sleep medicine aligns well with her desire to help patients find non-pharmacologic ways to improve their health. 

 In her spare time, she enjoys reading, quilting, basket weaving and drawing Zentangles. She is claimed by a Flat coat retriever named Kalaysi who is a problem solver and crazy about retrieving balls. 


Stacy Frazer, PA-C

Yuba City, CA

Stacy believes there is nothing more important than the quality of one’s sleep in regards to their overall health and well-being.  After graduating from the UC Davis PA program in 2011, she has worked locally in primary care for the last 7 years.  Her passion for health, wellness and physical fitness is evident in her care for her patients.  She’s an avid road cyclist and currently an ambassador for a cycling company.  Stacy grew up in agriculture in the north state and has a small farm raising dairy goats, chickens and pigs.


Tajinder Kullar, NP

Chico, CA

Tajinder joins Innovative Sleep Centers with an extensive background as a Registered Nurse in the surgical and rehab units at Enloe Medical Center in Chico, CA. In 2018 Tajinder received her Master of Science in Family Nurse Practitioner from Sonoma State University and her AANP board certification from the American Academy of Nurse Practitioners. Helping patients gain proper sleep treatment and improving their overall quality of life is her goal.  

In her off time Taj enjoys spending time with her family, reading and travelling the world especially back to India to visit family and friends.



Angela Hester, NP

Redding, CA

Angela Hester BSN, MSN, ACNP-BC. 

Angela graduated from Mercer University/Georgia Baptist College of Nursing in 1996. She worked as a Critical Care/Open Heart Nurse for 18 years and as an ICU Manager for 2 years. She graduated from Grand Canyon University in 2016 with a MSN as an Acute Care Nurse Practitioner - Board Certified. She worked at Mercy Hospital Redding as a Hospitalist for 2 years. 

 She believes that sleep hygiene is the key to overall good health and wants to extend good health practices in sleep to her patients.

 In her spare time, she works with a local animal rescue in rescuing and finding homes for feral cats and kittens. She fosters up to 20 - 30 cats/kittens at her "cat farm." Hobbies include hiking, camping, enjoying country life, and good friends.