Services We Offer

Discover how we can fulfill your gastrointestinal needs.

Our team of caregivers is eager to help with all of your digestive health needs. We provide thorough diagnostic evaluations and tailored treatment plans that work to make your life better. Let us help you optimize your gastrointestinal well-being.

Come to our brand new endoscopy suite for an exceptional quality procedural experience in an attractive setting.

Learn all the details.


These are some of the most common GI conditions that we have the expertise to care for.

  • GERD
  • Laryngopharyngeal reflux (LPR)
  • Barrett’s esophagus
  • Eosinophilic esophagitis
  • Celiac disease
  • H. pylori
  • Gastritis and ulcers
  • Functional dyspepsia
  • Irritable bowel syndrome
  • Crohn’s disease
  • Ulcerative colitis
  • Diverticulosis and diverticulitis
  • Hemorrhoids
  • Anal fissure
  • Anemia
  • Fatty liver
  • Abnormal liver tests
  • Weight management


These are some of the common symptoms people share with us. We help to clarify the diagnosis and offer effective treatment options.

  • Heartburn
  • Difficulty swallowing
  • Belching
  • Bloating
  • Nausea
  • Vomiting
  • Abdominal pain
  • Diarrhea
  • Constipation
  • Change in bowel habits
  • Blood in your stool
  • Weight loss
  • Weight gain

(224) 407-4400

Our multidisciplinary team works closely together to provide expert, patient-centered care for inflammatory bowel disease:


  • Highly regarded gastroenterologists with extensive experience in managing Crohn’s disease and ulcerative colitis.
    • All of our physicians offer routine colonoscopy, sigmoidoscopy, upper endoscopy, and capsule endoscopy studies.
  • Knowledgeable nurse practitioners who work closely with the physicians, provide comprehensive, evidence-based gastrointestinal care, and offer appointments for urgent needs.
  • Thorough evaluations including:
    • One-hour initial consultations
    • Comprehensive laboratory testing all available at our offices, including bloodwork and stool testing
    • Second opinions of gastrointestinal diagnostic studies performed at other locations
    • Several facilities conveniently located near our offices for advanced diagnostics including CT enterography, MR enterography, x-rays, and ultrasounds with access to records for quick turnaround of results
  • Specialized Registered Dietitians who offer consults for optimization of diet, correction of nutritional deficiencies, identification of dietary triggers, and management of coexisting IBS symptoms.
  • Designated IBD patient care coordinator to be your point of contact for medication refills, prompt communication of messages and results, and coordination of health maintenance items such as bone density scans, lab monitoring, and vaccinations.
  • In-office infusion suites specially designed for comfort, convenience, and close clinical monitoring.
  • Behavioral health specialists to help with various aspects of mental health care in patients with IBD, including anxiety, depression, pain, and coping.
  • Close collaboration with other specialties such as colorectal surgery and maternal-fetal medicine.
  • Efficient communication with other medical specialties that may be involved in IBD care including rheumatology, dermatology, radiology, and gynecology.

(224) 407-4400

Our infusion suites are a safe, private, and quiet environment to receive your medication infusions. Amenities include:

  • A qualified clinical infusion nurse who will perform all clinical monitoring during the infusion to ensure safety, continuity of care, and positive outcomes.
  • Private rooms with windows and WiFi.
  • Reclining chairs with pillows.
  • Snacks and beverages.
  • Convenient and close parking.
  • Often a less costly alternative to receiving infusions at other locations.
  • Close collaboration between your gastroenterologist and infusion nurse throughout the prescribed infusion treatment.

For questions or scheduling, please contact:

Comprehensive Gastrointestinal Health is always involved in several clinical trials to help further the care of gastrointestinal diseases. Take a look at what is currently ongoing:

  • Cessa: Evaluating the efficacy and safety of hydrocortisone suppositories in patients with ulcerative colitis.

If you are interested in participating in a clinical trial or have questions, please reach out to our research team at 224-236-3520 or via email at

Our knowledgeable registered dietitians will help to create an individualized plan that works for your lifestyle.

  • Thorough evaluation
    • Assessment of current nutritional status and nutrient deficiencies
    • Identification of food sensitivities
    • Realistic meal tracking plan
    • Individualized nutritional goals
  • Dietary treatments for GI conditions
    • Acid reflux (GERD)
    • Eosinophilic esophagitis
    • Celiac disease
    • Non-celiac wheat sensitivity
    • Irritable bowel syndrome
    • Crohn’s disease and ulcerative colitis
  • Nutritional strategies for maintaining wellness
    • Creating a healthy gut microbiome
    • Recommendations on supplements
    • Reducing risk of colon polyps and colon cancer
    • Reducing the risk of diverticulitis
    • Strategies for optimized athletic performance
  • Weight management
  • Personalized recipes and meal plans
  • Strategies for grocery shopping and eating out
  • Support and encouragement between office visits

Meet our resourceful Registered Dietitians.

Our behavioral health experts are comprised of a licensed medical family therapist and a clinical psychologist. They can work with you in a number of different ways with scientifically supportive interventions.

They offer the following services, depending on your specific needs and goals:

  • Cognitive Behavioral Therapy
  • Insight Oriented Therapy
  • Gut-Directed Hypnotherapy
  • Relaxation Strategies
  • Treatment of Depression, Anxiety, Stressors & Trauma
  • Coping Strategies for Dealing with a Chronic Illness or Suffering from Chronic Pain

The Weight Management program has additional information regarding psychological assessment, psychological support, and counseling.

Learn more about our behavioral health experts.

Strong evidence supports the idea that a combined intervention is far more effective for weight loss and maintenance than any single approach alone. Let our team of experts collaborate to help you achieve your goals.

Carrying excess weight is of particular relevance to gastroenterology because of the clearly documented impact extra weight has on numerous GI conditions, such as acid reflux, fatty liver, and the increased risk for colon polyps and colon cancer.

Our approach encourages:

  • Nutritional counseling
  • Psychological Assessment and Psychological Support
  • Improving sleep quality
  • Promoting physical activity
  • Optimizing the gut microbiome
  • Weight loss medications (when appropriate)
  • Referrals for endoscopic or surgical weight loss interventions (when appropriate)

We are closely following the latest discoveries about the role that the gut microbiome has in metabolism, as well as the role of gut hormones in appetite and weight regulation. We are eager to implement the next generation of therapies that emerge from these studies.

(224) 407-4400

We at Comprehensive Gastrointestinal Health are always looking for opportunities to educate our patients and the community about health and wellness. With this goal in mind, we are excited to announce our new webinar series: Nourishing Your Body, Soul, and Mind. This 6-part webinar series will consist of monthly lunch discussions created and led by our team of registered dietitians, clinical psychologists, and behavioral therapists. Webinars will occur at noon on the fourth Thursday of each month for the first half of 2024. The schedule is as follows:

#1: January 25, 2024 at 12pm

  • Topic: Habits that Last: Part 1
  • Presenter: Sharon Jedel, PsyD, Clinical Psychologist

#2: February 22, 2024 at 12pm

  • Topic: Cultivating a better relationship with Food
  • Presenter: Katrina Christianson, RD, Registered Dietitian

#3: March 28, 2024 at 12pm

  • Topic: Habits that Last, Part 2
  • Presenter: Sharon Jedel, PsyD, Clinical Psychologist

#4: April 25, 2024 at 12pm

  • Topic: Benefits of Cardio and Strength Training and How to Nourish for Both
  • Presenter: Amy Carson, RD, Registered Dietitian

#5: May 23rd, 2024 at 12pm

  • Topic: Intentional Self Care
  • Presenter: Jed Foster, LMFT, Behavioral Therapist

#6: June 27, 2024 at 12pm

  • Topic: You Are what You Eat: How Food affects your Mood and Gut
  • Presenter: Katrina Christianson, RD, Registered Dietitian

The webinars will consist of a 30-minute presentation followed by 15 minutes of questions and discussion. If you are interested in attending, please email The cost of virtual attendance is $15 per webinar. Register to participate in as many webinars as you would like. We are thrilled to be able to bring this virtual interactive educational opportunity to our patients and the broader community. We are hopeful that the experience will further enhance your own journey toward GI health and well-being.

Prehabilitation is the process of optimizing physical function prior to surgery to help improve the recovery process.

  • Prehabilitation training includes a combination of:
  • Nutrition
  • Mental preparation
  • Exercise and strength training

Let our team help you prepare for your upcoming surgery.

(224) 407-4400

Patients often report extensive diagnostic evaluation followed by a sense of abandonment after the testing is over. We aim for better follow through and meaningful results.

  • Emphasis on medical education to empower your ability to impact your own gastrointestinal health
  • Frequent appointments to assess progress and tailor your treatment plan
  • Coordination of the comprehensive approach to challenging conditions such as irritable bowel syndrome, inflammatory bowel disease, and weight management
  • Health maintenance – we not only want to help get you well, but also keep you that way.
  • Disease prevention – we will guide you on the latest research that can help try to prevent disease and enhance wellness.

(224) 407-4400

  • Dr. Troy and her staff are professional, caring, and committed to providing a comprehensive solution for your diagnosis. I highly recommend them.
    Catherine A. Patient
  • Thanks Dr. Troy for seeking to find solutions to my pain, not just band-aid the problem! You are a wonderful and patient doctor that listens so well! Every step of the way your staff was approachable and professional from the moment I stepped in the door.
    Lydia C. Patient
  • Everyone was helpful and very pleasant. The office is beautiful and functions very efficiently.
    Kathy L. Patient
  • The team is awesome! The care, concern, speed of results, communication and friendliness is one of the best experiences I have ever had within the medical field. Thank you for everything you do it is greatly appreciated! 2/15/19
    Rick A. Patient
  • I have had Ulcerative Colitis for over 20 years now and have seen many GI doctors but none as wonderful as Dr. Troy. She truly takes her time to listen and be completely through. She is an amazing doctor and I wish more doctors shared her wonderful disposition and ability to care about her patients.
    Erin P. Patient
  • Dr. Troy and her staff are incredibly caring and thoughtful! She answered every question and spent quality time. I highly recommend her.
    Ann C. Patient
  • I had an amazing experience and they made me feel very comfortable despite having to drink the prep solution all night long. They were very kind and took care of me very well. Dr. Troy was very caring and explain everything perfectly. I would totally recommend!
    Hannah W. Patient
  • The offices are new and clean and relaxed; they don't feel clinical. I especially enjoyed the creative use of toilet paper as tastefully placed wall decor in the clinic bathroom. Someone has a sense of humor! Staff was friendly, professional and efficient. Being able to choose music and post procedure snack options was surprising. Taking home a printout of the procedure with colored photos and an explanation was an amazing use of technology seemed almost magical, especially coupled with the Lindor chocolates. Thank you! The staff managed to turn an unpleasant procedure into a pleasant experience.

    Nancy R. 2/27/18
  • Dr. Troy and her team are constantly excellent. Everyone is on board to deliver a high-quality experience. It’s a team effort.
    Evelyn B. Patient
  • Everyone is very helpful. Liz Moon has been excellent with follow-up and care. I highly recommend the team and practice. 
    Kimberly N.  Patient
  • Everyone is so knowledgeable and caring. It all starts when you walk in the front door to the point of the end of your appointment! 
    Wendy B.   Patient
  • I am very, very pleased with the exceptional care both from the staff and Dr. Nathanson. One feels that they are the most important patient on the rosterGreat doc, great staff, great location
    Barbara G.   Patient
  • Dr. Troy and her staff were amazing! The billing department and Veronica went above and beyond to assist with an insurance issue and make sure all was ready to go for my procedure. Everyone was helpful and really worked to explain everything and put me at ease. I cannot recommend this office enough! Thank you for making an unpleasant procedure as pleasant as it could possibly be
    Kelly S.  Patient
  • Whenever I need Comprehensive Gastrointestinal Health’s services, I always know I am in good hands from start to finish. 
    William G.   Patient
  • Very friendly, helpful staff and great location! Dr. Nathanson is very caring, knowledgeable, and easy to understand. He has the ability to explain issues to the patient and make sure patient understands. 
    Oksana S.  Patient
  • Seeking out treatment for chronic medical conditions is a really scary and intimidating experience. I was so comforted by my first visit to Comprehensive Gastroenterology. My medical provider spent almost an hour with me getting to know me and my entire medical history, taking thorough notes, and paying attention to me not only as a patient but also as a person. I felt seen and heard which is something that can be very rare these days in healthcare. I'm really looking forward to the coming months of treatment with these providers and am really grateful for a great first visit. 
    Shannon L.  Patient
  • Dr. Nathanson is always a class act: professional, attentive, and most of all kind and caring. The new office and staff are a compliment to the Dr. and demonstrate a stellar example of how medical care should be delivered to all. Thank you again to the whole crew for a smooth experience for my colonoscopy! 
    Janet W.  Patient
  • Dr. Troy spent time to tell me about findings and recommendations. Lots of staff prior to the appointment to ask me if I needed anything - very attentive. 
    Jennifer D.  Patient
  • I highly recommend this practice. They have timely communication with patients, it was easy to make an appointment, the pre-procedure instructions were very thorough, and the staff, nurses, and doctors were very friendly and knowledgeable. My experience here was 100% better than my previous colonoscopy at a nearby suburban hospital.
    Brenda M.  Patient
  • My primary doctor recommended this practice. I was very happy. Staff listens and is very patient and friendly. I am very nervous about needles, but it was very smooth and relatively painless
    Caroline B.  Patient
  • These procedures are not very fun, but they do everything to make you feel comfortable and are professional. If you need this done, this is the place to go. The staff is very friendly and the doctors are accessible and friendly. 
    Paul V.  Patient
  • The entire experience was very smooth and pleasant. Dr. Troy and her staff are all very positive and professional. And the Mobile Anesthesia team could not have been nicer and professional. I was completely at ease throughout the experience. 
    Catherine C.   Patient
  • This process was seamless. The quality of care and the detailed instructions on a regular basis were great reminders for me. I knew exactly what I needed to do before the procedure. Everyone at the facility was kind and knowledgeable. Everything was clean. I would never do this procedure at a hospital. I’m recommending it to all my friends. Thank you, you are all very good at what you do. 
    Maureen L.  Patient
  • What a breath of fresh air! Dr. Nathanson was kind, considerate, a great listener, and really spent a lot of time with me. After being left hanging by another practice that didn't answer my questions and just left me hanging for months, this was so refreshing. I'm confident they will provide me with excellent care moving forward. 
    Jonathan M.  Patient
  • While getting a colonoscopy is not fun, Comprehensive Gastroenterology made the whole experience as comfortable as possible. From simplifying the preparation, through executing the procedure at an outpatient clinic
    Ellen R.  Patient
  • From the minute you walk in the door the staff is very friendly. Nurses are very informative. The procedure was so quick and painless. I highly recommend this practice! 
    Karin S.   Patient
  • I had a wonderful experience! The staff were incredibly kind, and they made me feel right at home and went over the top to make sure I felt comfortable. It was truly the best experience I’ve had with a scope before
    Autumngrace P.  Patient
  • Excellent care, I highly recommend Comprehensive Gastrointestinal Health. Everyone went well above and beyond to make my experience convenient, comfortable and pleasantI love the entire staff and especially Dr. Nathanson! 
    Marcia J.  Patient
  • Excellent care! My first upper GI endoscopy and my second colonoscopy were done here. Hardly any waiting (much faster than at a hospital), really good instructions for the colonoscopy prep (I appreciated the vegan meal ideas as I am a vegetarian). Everyone treated me with respect and care, and it was a relief to finally get diagnosis for my GI issues. 
    Susanne B.  Patient
  • Dr. Tara Troy and Comprehensive GI Health stands for excellence. Very professional and caring at the same time. They are so detailed in setting appointments. The prep is amazing and everything up to the procedure, is perfect. It’s 150% Perfect. I highly recommend this place and Dr. Tara Troy. They are really fitted to be in a medical field. They are so caring and explained thoroughly pre and post procedure. The Mobile Anesthesiologist that they worked with are also excellent.
    Zenaida B.   Patient
  • This establishment is top-notchThey get you in and out in a timely mannerThey are very professional. The place is very cleanAll staff members were genuinely friendly and cared about what they were doing. 
    Norman H.  Patient
  • The experience exceeded my expectations. Everyone was attentive, kind and extremely knowledgeable. Given the nature of the visit I was made to feel comfortable and still can’t believe how easy and effortless the whole experience was. I would highly recommend choosing this office and staff for your health needs. 
    Jennifer H.  Patient
  • Olivia and the phlebotomist that worked with me were so nice, professional and welcoming. I let them know ahead of time that I am typically not an easy blood draw due to rolling or small veins and both were amazing. 
    Shannon P.   Patient
  • Fantastic and efficient care with flexible hours for busy professionalsThe staff is very courteous and helpful, and the providers listen to your concerns. 
    Kim T.  Patient
  • Each and every person I encountered at this practice was professional, competent, and extremely kind. Very knowledgeable. Highly recommend. 
    Jacqueline E.   Patient
  • Everything about this practice is EXCELLENT from the scheduling, staff, email/text correspondence, anesthesia staff, and the amazing physicians. I have had a colonoscopy with both doctors & would highly recommend both of them. I was ESPECIALLY IMPRESSED by my anesthesiologist. AMAZING & SO CARING 🙂 This practice is TOP NOTCH!!!! 
    Pamela N.   Patient
  • The day of procedure was everything I’d love medical care to be—on time but not rushed, opportunity to ask questions, everyone was friendly, environment seeded with the feeling of competence…everyone gave the vibe of confidence in their ability to provide exceptional care. Couldn’t have been happier with my first colonoscopyPre-procedure instructions were clear and easy to follow which resulted in a good prep. Follow up after procedure was clear and concise.
    Emily V.  Patient

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Call us at (224) 407-4400 for an appointment to receive top quality healthcare.