Respiratory Virus and Vaccine Information

Alexander S. Tosiou, MD

4.9

1528 ratings Read Reviews

Northwestern Medical Group

Primary Specialty

Gastroenterology

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Education

Medical Education:: MD, Loyola University Stritch School of Medicine - 1993
Residency:: McGaw Medical Center of Northwestern University - 1996
Fellowships:: Advocate Health Care (Advocate Lutheran General Hospital) - 1999

Board Certifications

American Board of Internal Medicine/Gastroenterology - Gastroenterology (Certified)

Faculty Profile

Clinical Assistant Professor, Feinberg School of Medicine

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Practice Groups and Affiliations

Medical Group:: Northwestern Medical Group
Alignment Category:: Northwestern Medicine Physician Network
On Medical Staff At:: Catherine Gratz Griffin Lake Forest Hospital

Grayslake Ambulatory Surgery Center

Ratings and Reviews

At Northwestern Medicine, our patient’s feedback is important to us. While different care providers have their own unique strengths, we strive to be as transparent as possible with our quality of care.

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Overall Rating

4.9

4.9

1528 Ratings

Reviews from Patients

100 Most Recent Reviews

Reviews from Patients

100 Most Recent Reviews

February 25, 2026

5.0

Very thorough

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February 24, 2026

5.0

Excellent doctor

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February 19, 2026

5.0

Comes highly recommended by my PCP.

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February 13, 2026

5.0

Fabulous and very knowledgeable and current. Willing to work with patient to find best treatment plan. Open for discussion without exhibiting condescending attitude. He's a keeper

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February 09, 2026

5.0

His office let me know about my procedure and what was required for me to have comply with the preparation beforehand. He greeted me before I had my test and inquired if I had any questions. My results of my testing were explained when I woke up with pathology results to be sent to me within a week.

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February 09, 2026

5.0

He was empathetic and thorough. He explained the entire procedure. His office was so caring. They are a lovely team.

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February 02, 2026

5.0

He was fast, made it easy with a clear explanation and opportunity to ask questions.

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January 27, 2026

5.0

Honestly, I don't remember much. But my husband said he explained how things went very clearly.

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January 23, 2026

5.0

Very professional

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January 21, 2026

5.0

Dr. Tosiou is very thorough and goes over everything in detail with me. He's open for any questions and treats me with respect.

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January 19, 2026

5.0

Thorough and professional

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January 19, 2026

5.0

Attentive and professional staff. All off my needs were met with careful attention to all aspects of my care.

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January 19, 2026

5.0

He is very knowledgeable. I have a lifelong condition & he will work with my current problems. Great finding him.

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January 12, 2026

5.0

Dr. Tosiou is very professional and cares for his patients. He is always on top of test results and has a very good knowledge of what he does. He gives his patients the necessary time and always listens to the concerns that are brought to him.

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January 05, 2026

5.0

Great doctor!

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January 02, 2026

5.0

Great doctor.

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January 02, 2026

5.0

Great Doctor- thorough and intelligent

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December 23, 2025

5.0

a great doctor

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December 22, 2025

5.0

Great Doctor!!

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December 19, 2025

5.0

He is the best! He explained the procedure and keep you at ease.

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December 15, 2025

5.0

Great doctor in every way

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December 05, 2025

5.0

Very thorough and professional.

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December 05, 2025

5.0

Very thorough, good explanations of procedure, findings and next steps. Went out of his way to make time in his packed schedule for a necessary follow-up once initial findings were back. Very much appreciate all aspects of the care provided by Dr Tosiou.

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December 05, 2025

5.0

Excellent doctor

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November 29, 2025

5.0

A real pro!

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November 24, 2025

5.0

Competent GI specialist and attentive to my needs

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November 24, 2025

5.0

Excellent MD. Very friendly and down to earth but also very skilled and professional. Great experience.

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November 24, 2025

5.0

Told me exactly what will happen for treatment.

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November 24, 2025

5.0

Dr. Tosiou is very thorough and and asked many questions regarding my symptoms. I feel as though he is seriously invested in my concerns.

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November 24, 2025

5.0

He got down to business but kindly explained what his plan was for my issue. I appreciated that.

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November 23, 2025

5.0

He always go in details, so you feel comfortable.

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November 21, 2025

5.0

We trust Dr Tosiou and have used him for over 20 years.

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November 21, 2025

5.0

He is very personable, knowledgeable and skillful.

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November 21, 2025

5.0

Friendly and asked questions and listened. Paid attention to my concerns and didn't rush me. Spent time talking!

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November 17, 2025

5.0

Awesome

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November 17, 2025

5.0

See above as well as he was Educational, ansewered all our questions. Told us his findings.

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November 17, 2025

5.0

Very kind, full of information My niece is a patient and very happy with him

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November 14, 2025

5.0

Dr Tosiou is amazing GI doctor and takes his time explaining

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November 12, 2025

5.0

He takes as much time as necessary to have answer any questions I might He listens

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November 11, 2025

5.0

He came up with a plan to monitor my situation

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November 10, 2025

5.0

He wasn't a great listener and provided information regarding my upcoming colonoscopy

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November 10, 2025

5.0

Dr. Tosiou has done all of my colonoscopy exams. He is caring and highly skilled and has my trust!

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November 10, 2025

5.0

Dr Tosiou always takes the time to thoroughly go over any concerns, and explore options for treatment. I never feel rushed, and he genuinely cares about achieving a successful outcome.

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November 10, 2025

5.0

Very clear in answering questions and giving information.

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November 09, 2025

5.0

Great doctor all went smooth

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November 07, 2025

5.0

Friendly and knowledgeable staff.

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November 07, 2025

5.0

Dr Tosiou is always kind, professional, thorough & caring. I never feel rushed at my appointments.

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November 04, 2025

5.0

Did a great job and was very helpful.

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November 03, 2025

5.0

I really liked him. He listened and repeated everything I said back to me.. He looked at hospital reports and asked me a lot of questions to understand what I was going through. I appreciated his professionalism. He explained the reasons why he wanted certain tests to be done.

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November 03, 2025

5.0

Dr. Tosiou was professional and efficient, great bed side manner's.

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November 03, 2025

5.0

he is an experienced and good doctor

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October 31, 2025

5.0

Takes time to explain, answer questions.

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October 31, 2025

5.0

He was very thorough in explains the procedure and introduced me to all the other attending staff during my procedure

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October 31, 2025

5.0

Very professional. Felt safe, well cared for by a competent professional

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October 29, 2025

5.0

He was capable and a good communicator.

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October 29, 2025

5.0

Smart, thorough, speaks in a way that the patient understands

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October 28, 2025

5.0

His confidence prior to the procedure put me at ease.

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October 27, 2025

5.0

The best

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October 24, 2025

5.0

Very professional and knowledgeable

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October 21, 2025

5.0

Always does great work

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October 16, 2025

5.0

Best in Field

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October 15, 2025

5.0

He is wonderful. He listens, and explains conditions and the reasons for his care and treatment recommendations.

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October 13, 2025

5.0

He was super nice, explained everything really well and really listened to what I had to say.

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October 13, 2025

5.0

Easy to talk with and explained things very well

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October 13, 2025

5.0

Absolutely terrific

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October 13, 2025

5.0

Firm and honest

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October 11, 2025

5.0

Dr. Tosiou is a good Dotor. It was my first time meeting him, but the visit with him let me know that I was seeing someone who takes his work seriously.

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October 10, 2025

5.0

Informative Timely Pleasant

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October 10, 2025

5.0

He is an extraordinary doctor, he cares about finding solutions for my condition, he is an eminence

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October 07, 2025

5.0

No real comments. I saw him for only a few minutes before I was out, and I wasn't really with it afterwards.

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October 03, 2025

5.0

Very professional, very good

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October 03, 2025

5.0

Dr Tosiou listens to what I have to say and involves me in the plan of care

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October 01, 2025

5.0

As I am unconscious during most of my time with Dr. Tosiou, all I can comment on is the rest of the staff and about 60 seconds chatting.....

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September 30, 2025

4.0

I am a returning patient after 20 years and haven't spent enough time with him yet.

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September 29, 2025

5.0

Keeps patient well informed.

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September 29, 2025

5.0

Top quality doctor, with an efficient, helpful staff.

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September 28, 2025

5.0

He's kind and doesn't rush. Explains well.

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September 26, 2025

5.0

Dr Tosiou is always kind, professional, thorough and includes me in the discussion about treatment. Great doctor!!

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September 23, 2025

5.0

Very nice, clear explanations.

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September 22, 2025

5.0

He couldn't have been nicer or better.

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September 20, 2025

5.0

For your interest and dedication in finding a solution for my treatment.

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September 19, 2025

5.0

HE IS PROFESSIONAL, COURTESY TAKES TIME TO ANSWER ALL YOUR QUESTIONS

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September 19, 2025

5.0

Solid across the board. No complaints

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September 17, 2025

5.0

Very caring and very thorough.......very grateful for his expert care.

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September 17, 2025

5.0

Dr. Tosiou goes above and beyond and epitomizes All attributes stated previously, including compassion for All patients. His focus in patient-health care is #1.

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September 15, 2025

5.0

He is competent and professional yet he has a very good bedside manner. He's very kind.

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September 05, 2025

5.0

I have been seeing Dr. Tosiou every 5 years and I am very happy with the services.

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September 04, 2025

5.0

He was very professional, and extremely thorough. He explained any questions I had so I could understand the process and the importance of following the directions.

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September 01, 2025

5.0

My doctor for years

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August 30, 2025

5.0

He's the best, been my Dr. for years.

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August 29, 2025

5.0

Made me feel comfortable about the procedure

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August 29, 2025

5.0

Explained procedure clearly

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August 29, 2025

5.0

Dr is well prepared and very knowledgeable.

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August 28, 2025

5.0

Pleasant and thorough

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August 25, 2025

5.0

He was the doctor I had for my procedure ten years ago and his bed side manner is still the same assuring and friendly he is very capable

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August 24, 2025

5.0

Good bedside manner and an experienced professional.

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August 23, 2025

5.0

Very knowledgeable and professional.

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August 19, 2025

5.0

The best GI Doc in the Chicagoland Area

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August 19, 2025

5.0

Dr Tosiou made me feel comfortable and answered all our questions. I found him to be very knowledgeable. I would definitely recommend him to anyone looking for a GI doctor.

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August 15, 2025

5.0

Really thorough and listens and tries to take care of the problem

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Disclosures

Alexander S. Tosiou, MD reported no external professional relationships for calendar year 2024.

External Professional Relationships

Pharmaceutical, device, and biotechnology companies frequently collaborate with basic scientists and physicians within an academic medical center to help advance science and improve patient care. These relationships are important in achieving scientific breakthroughs and in establishing the effectiveness and safety of promising new therapies. In order to assure objectivity in clinical research and patient care, the Northwestern University Feinberg School of Medicine (Feinberg), Northwestern Memorial HealthCare, Children's Hospital of Chicago Medical Center, and the Shirley Ryan AbilityLab have adopted integrity policies that require research and clinical faculty (in full-time, part-time, and unpaid/voluntary categories) to report compensated and uncompensated external industry relationships. Patients are encouraged to discuss these disclosures with their physician as well as to inquire as to how these relationships are overseen by Feinberg. To learn more about our Disclosure and Professional Integrity Policy, and the conflict of interest policies of our joint affiliate survey partners, please go to our Office for Regulatory Affairs Policies page.

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