About Us

Internal Medicine and Holistic Medicine Combined

Get to the root cause.

We use techniques to treat the root cause of a patient’s condition without the use of pharmaceuticals. We design programs to detoxify and build, using nutrition and nutraceuticals customized to each individual’s needs. We combine this with a strong focus on mind/body support to prevent or reverse physiological changes in the body.

A Message From Our Founder

Welcome! I’m Dr. Karen Sun, founder of the Integrative Wellness Center in Orange County, California, and board-certified in both Internal Medicine and Integrative & Holistic Medicine.

After facing my own struggles with menopause, gut issues, and the limitations of conventional care, I discovered powerful, evidence-based solutions—like bioidentical hormone pellet therapy, personalized nutrition, detox, and regenerative treatments. These treatments transformed my health, and now transform the lives of my patients. Some of these really effective evidence-based solutions I found over the years was captured in my first book : Vitality Now – A comprehensive guide to anti-aging, rejuvenation and vibrant health.

From fatigue and mood swings to gut imbalance and stress, I treat the root causes, not just the symptoms. Whether you’re searching for answers after years of frustration or simply want to slow the aging process and feel your best, I’m here to help. Let’s create a personalized plan so you can thrive – stronger, healthier, and more vibrant than ever.

Dr. Sun's degrees and certifications

Fellowship: UC Irvine, Long Beach VA Hospital

Residency: Mt. Sinai Hospital, Chicago, IL

Medical School: National Taiwan University

Annie's degrees and certifications

Master of Science in Nursing/Family Nurse Practitioner: University of Phoenix
Master of Arts in Psychology: Pepperdine University
Bachelor of Science in Nursing: UCLA

Annie Tak, FNP-C / MSN

Nurse Practitioner Annie joined the Integrative Wellness Center in 2019 and quickly became a key partner to Dr. Karen Sun in delivering exceptional care. She holds a Master of Science in Nursing/Family Nurse Practitioner from the University of Phoenix, a Master of Arts in Psychology from Pepperdine University, and a Bachelor of Science in Nursing from UCLA. With a strong background in Internal Medicine and aesthetics, Annie specializes in bio-identical hormone therapy and leads our Aesthetic Program, offering BOTOX, and JUVEDERM to help patients look and feel their best.

Outside the clinic, Annie is a certified group fitness trainer who enjoys Pilates, kickboxing, and running marathons—living the vibrant, balanced lifestyle she inspires in others.

“Even if I knew the world was to end tomorrow, I would still plant my apple tree today!” -Martin Luther

Existing Patient Appointment Scheduling

What Patients Are Saying

Pellet therapy works!

My stamina, mental clarity, and libido have all improved with the pellet therapy. I also have less bloating and stomach issues with the supplements Dr. Sun recommended to me.

Steven R.

Dr. Sun really listens

I am so very satisfied with my experience at the IWC. Dr. Sun really takes the time to listen to my concerns and provides great advice and feedback. She is very understanding and offers great progressive alternatives to addressing health issues. Thank you for all that you do Dr. Sun!

Sandy A.

Spread the word! Symptoms are gone!

Spread the word! I was on synthetic hormones for over 10 years with minimal improvement. I suffered from hot flashes and night sweats, disrupted sleep, low energy, and lack of libido. Pellet therapy has greatly improved my quality of life now that my symptoms are gone!”

Joyce C.

More energetic than my 30’s!

The bio-identical hormone pellet therapy has given me my life back. My marriage is stronger and I feel better and more energetic than I did in my 30’s!”

Susan V.

No more hot flashes

Tell the world about it! Women and men need to know about the bio-identical hormone pellet treatment! Dr. Sun has changed my life for the better, no more hot flashes, irritability, night sweats, depression, weight gain, and memory issues. Thank you Dr. Sun!

Terri B.

So convenient and definitely recommended!

I definitely recommend Dr. Sun’s bio-identical hormone pellet treatment to all my family and friends! It is so convenient not having to take a daily pill or worry about hormone creams rubbing off too soon before they are absorbed. I no longer suffer from recurrent bladder infections, insomnia, irritability, and memory problems.

Isa D.

I’m my “old self” again!

After suffering from fatigue, depression, low energy and un-clear thinking I tried hormone cream and patches that gave me no relief. I started the pellet therapy with low expectations and was amazed when all my symptoms disappeared. My energy increased and I felt like my “old self” once again! I highly recommend the pellet therapy to all women, there is no reason why we should “suffer” with menopause.

Marie K.

Pellet therapy is easy and painless

First, I recommend bio-identical hormone therapy no matter what type. But after trying oral medication and cream I strongly recommend pellet therapy. It is easy and painless and I only have to visit the doctor every 4-5 months!

Susan D.

Start Your Wellness Journey Here

We’re standing by to help you with our unique combination of internal and holistic medicine practices. We can’t wait to meet you on your wellness journey!