Unio Specialty Care – Gastroenterology – Oxnard

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Unio Specialty Care – Gastroenterology – Oxnard

Office Hours

Monday

8:00 am - 5:00 pm

Tuesday

8:00 am - 5:00 pm

Wednesday

8:00 am - 5:00 pm

Thursday

8:00 am - 5:00 pm

Friday

8:00 am - 4:00 pm

Saturday

Closed

Sunday

Closed

Office Hours

Monday

8:00 am - 5:00 pm

Tuesday

8:00 am - 5:00 pm

Wednesday

8:00 am - 5:00 pm

Thursday

8:00 am - 5:00 pm

Friday

8:00 am - 4:00 pm

Saturday

Closed

Sunday

Closed

Ashwinee Condon, MD

Dr. Ashwinee Condon is board-certified in gastroenterology and advanced endoscopy. She has extensive GI training at UCLA, first completing her general gastroenterology fellowship, and then staying on for an additional year for training in specialized GI procedures.

Jessica Fennewald, NP

Jessica completed her Bachelors of Science in Nursing at University of Missouri-Columbia in 2004. She started practicing at St. Luke’s Hospital in St. Louis, Missouri in the telemetry/Intensive Care Unit. Shortly after, she completed her Master’s degree at Maryville University in St. Louis, Missouri in 2010.

Jay Guan, MD

Dr. Jay Guan has extensive training in a broad range of GI disorders and procedures. His clinical focus includes Inflammatory Bowel Disease, Barret’s Esophagus, NASH, GI motility disorders, Hepatitis B/C, and Eosinophilic Esophagitis.

Karen Simon, MD

Dr. Karen Simon received her B.A. from Stanford University in 1996. She then attended Northwestern University for medical school.

Micha Rojany, MD

Dr. Micha Rojany was born and raised in Southern California. He received his undergraduate degree from the University of California, Berkeley. After, he attended USC Medical School and completed his internship and residency at Cedars-Sinai Medical Center in Los Angeles.

Justin Marasigan, DO

Dr. Justin Marasigan was raised in the Los Angeles area. He earned his undergraduate degree from the University of Southern California and his medical degree from Kirksville College of Osteopathic Medicine in Missouri.

Choose a Provider Below to Schedule an Appointment

If you are an existing patient, please select your provider

Justin Marasigan, DO

Micha Rojany, MD

Karen Simon, MD

Jay Guan, MD

Jessica Fennewald, NP

Ashwinee Condon, MD

Reviews

We have moved! Our new office location is 1200 W. Gonzales Road, Suite 100 in Oxnard, CA.

Expert Gastroenterology Services in Oxnard – Accepting New Patients

At Unio Specialty Care – Gastroenterology in Oxnard, our board-certified physicians provide comprehensive digestive and liver care in a convenient clinic located off Wankel Way. We’re now accepting new patients and accept most major insurance plans.

Whether you’re due for colon cancer screening, dealing with chronic GI symptoms, or monitoring liver health, our experienced team provides tailored diagnostics and treatments.

Colonoscopy & colorectal cancer screening
Upper endoscopy (EGD)
Flexible sigmoidoscopy & capsule endoscopy
ERCP & endoscopic ultrasound (EUS)
Liver evaluation & FibroScan testing
Hemorrhoid banding therapy
SIBO breath testing & nutrition counseling

Serving patients from:

Oxnard
Ventura
Port Hueneme
Camarillo
Saticoy
El Rio
Channel Islands Beach
Nyeland Acres
Somis
Santa Paula
Moorpark
Ojai
Fillmore
Newbury Park
Thousand Oaks
Santa Rosa Valley
Casa Conejo
Meiners Oaks
Westlake Village
and surrounding Ventura County communities.

GI conditions we treat at our Oxnard GI Clinic

We treat a full range of gastrointestinal and liver conditions, including GERD, IBS, Crohn’s disease, ulcerative colitis, liver disease, and more. Preventive colonoscopy screenings are also offered.

We are accepting new patients for colon cancer screening

Our Oxnard GI doctors welcome new patients for colon cancer screening, including routine colonoscopy and follow-up testing for high-risk individuals. We recommend patients aged 45 and older schedule a screening appointment.

What to expect during your first gastroenterology appointment

At your first visit, our team will gather your medical history, review symptoms, and discuss any GI concerns. We’ll develop a diagnostic or treatment plan tailored to you, which may include procedures like an upper endoscopy or colonoscopy.

What is a colonoscopy and how to prepare

A colonoscopy is a highly effective screening tool to detect colon cancer, polyps, and inflammation. Prior to your procedure, we’ll provide detailed prep instructions and sedation options for your comfort.

Conditions We Treat at the Oxnard GI Clinic

Our gastroenterologists specialize in treating:

Acid reflux (GERD)
Irritable Bowel Syndrome (IBS)
Inflammatory Bowel Disease (Crohn’s & ulcerative colitis)
Constipation & diarrhea
Colon polyps & colorectal cancer
Celiac disease
Liver disease & hepatitis
Gallbladder & pancreatic disorders
Hemorrhoids & anal fissures

GI Services Offered at Our Oxnard Office

We offer:

Colonoscopy in Oxnard
Flexible Sigmoidoscopy
Upper Endoscopy (EGD)
Capsule Endoscopy
Liver function testing
Hemorrhoid Banding Therapy
SIBO breath testing
ERCP & EUS
Nutrition counseling & dietary support

Our team uses the latest tools and technology to provide minimally invasive, highly accurate care.

Frequently Asked Questions

Do I need a referral to see a GI doctor in Oxnard?

Depending on your insurance plan, a referral may be required. Our team will verify your benefits when scheduling.

What conditions do you treat at this Oxnard location?

We manage GERD, IBS, IBD, liver disease, gallbladder disorders, colon polyps, hemorrhoids, and more.

Is this clinic in-network with my insurance?

Yes — we accept most major insurance plans. We’ll confirm your coverage prior to your visit.

Do I need to fast before my appointment?

Fasting is only necessary if you are scheduled for a procedure such as a colonoscopy or endoscopy.

Will tests be done on my first visit?

Your first visit is typically consultative. Any necessary testing or procedures will be scheduled separately.

Do you offer colon cancer screening in Oxnard?

Yes — we provide colonoscopy and related screening services, typically starting at age 45 or earlier based on risk factors.

Highly Reviewed Gastroenterologist in Oxnard, CA

Doctors at Unio Specialty Care Gastroenterology, an affiliate of Unio Health Partners, in Oxnard, CA have hospital or surgery center affiliations with:

Camarillo Endoscopy Center and Channel Islands Surgical Center
Camarillo Endoscopy Center
CMH Ventura
Pleasant Valley Camarillo
St. Johns Regional Oxnard

Ready to Make an Appointment?

We are the largest gastroenterology physician group in California. Our organization is committed to providing high-quality, patient-centered care in a private practice setting. Our physicians are experts in the diagnosis and treatment of diseases of the gastrointestinal system, including those of the esophagus, stomach, colon, liver, small intestine, gallbladder, pancreas, and biliary tract.

Make an appointment today to start your journey to better health!