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About Us
Welcome To
The Derm Collective
North Shore
Our new dermatology practice, co-founded by board-certified dermatologists Dr. Rachel Pritzker and Dr. Todd Johnson, offers premier clinical dermatologic care specializing in general and surgical dermatology, Mohs surgery, and aesthetics. We prioritize preventive care and support healthy skin aging, aiming to be your dedicated resource in achieving and maintaining optimal skin health.
Todd A Johnson, MD
Board-Certified Dermatologist | Mohs Micrographic Surgeon
A graduate of the University of Illinois Medical Center with over 20 years of clinical experience in both community and academic settings, Dr. Johnson is a distinguished board-certified dermatologist with expertise in general dermatology, surgical dermatology, and Mohs micrographic surgery. Known for his patient-centered approach, he provides comprehensive care that prioritizes patient comfort and understanding, fostering a trusting environment where patients feel heard and valued
Dr. Johnson is a fellow of the American Academy of Dermatology and the American Society of Mohs Surgery. He is also an active member of the American Society for Dermatologic Surgery, American Academy of Dermatology, International Dermoscopy Society and the Chicago Dermatologic Society
His extensive training and expertise enable him to deliver exceptional care for a wide range of skin conditions, utilizing cutting-edge techniques and personalized treatment plans. He specializes in diagnosis and treatment of skin cancer using techniques such as dermoscopy, whole body skin mapping, topical preventive and therapeutic chemotherapy and Mohs micrographic surgery.
Outside of his practice, Dr. Johnson is passionate about conservation and land stewardship in Northern Illinois and the Driftless area of Southwest Wisconsin. He and his wife, a biochemistry professor at the University of Illinois, enjoy family life with their daughter and two rescue dogs, Petey and Cash.
Specialties: Skin Cancer Diagnosis, Detection, and Treatment; Dermatologic Surgery, MOHS Micrographic Surgery, Dermoscopy, General Dermatologic Care, Neurotoxin procedures.
Rachel N Pritzker, MD
Fellowship-Trained, Board-Certified Dermatologist
Dr. Pritzker graduated Phi Beta Kappa with a bachelor’s degree from Emory University where she was recognized as a member of the Alpha Omega Alpha Honor Society, and earned her medical degree at Rush University. She completed her dermatology residency at Cook County Hospital in Chicago, followed by a distinguished fellowship in Laser, Cosmetic, and Dermatologic Surgery at SkinCare Physicians in Boston, collaborating with clinical faculty from the dermatology departments of Harvard and Yale.
An active voice in the dermatologic community, Dr. Pritzker frequently speaks at both local and national dermatology meetings and has published numerous articles in peer-reviewed journals and dermatologic textbooks.
Dr. Pritzker is a member of several professional organizations, including the American Academy of Dermatology, American Society for Dermatologic Surgery, Women’s Dermatologic Society, the American Society for Laser Medicine & Surgery, and the Global Aesthetics Conference. In addition to her clinical practice, she serves as a consulting physician at Cook County Hospital and is dedicated to teaching dermatology residents, sharing her knowledge and passion for the field.
Dr. Pritzker was raised in the North Shore of Chicago, where she currently resides with her husband and children. In her free time, she enjoys spending time with her family, traveling, and hiking.
Specialties: General dermatology, dermatologic surgery, cosmetic injectables (Botox Cosmetic, Dysport, Daxxify, RHA fillers, Juvéderm, Restylane, Sculptra, Radiesse), and laser procedures.
MEGAN PARSONS, FNP-BC
BOARD-CERTIFIED FAMILY NURSE PRACTITIONER
Megan Parsons is a board-certified Family Nurse Practitioner with a passion for dermatology and a commitment to delivering compassionate, patient-centered care. Certified by the American Nurses Credentialing Center and licensed as both an Advanced Practice Registered Nurse (APRN) and a Registered Nurse (RN) in the state of Illinois, Megan brings a wealth of clinical expertise and a thoughtful approach to every patient interaction.
Before specializing in dermatology, Megan spent four years honing her clinical skills as a critical care nurse. Her experience spans pediatric, neonatal, and cardiac intensive care units, where she developed a strong foundation in critical thinking, evidence-based practice and holistic patient care. Her passion for dermatology led her to the field in January 2023, where she gained experience working as a nurse at a Northwestern Dermatology Practice. She started at The Derm Collective North Shore in February 2025, where she received specialized training from Dr. Johnson and Dr. Pritzker.
Megan is known for her warm, approachable demeanor and her dedication to fostering long-term relationships with her patients. She believes in a collaborative, holistic approach to health—listening carefully, educating thoroughly, and tailoring treatment plans that align with each patient’s unique needs and lifestyle. As a Nurse Practitioner, she is proud to offer a model of care that emphasizes whole-person wellness, clinical excellence, and accessibility.
Megan earned her Master of Science in Nursing from Vanderbilt University, where she graduated from the Family Nurse Practitioner Program in 2024. She began her nursing career after receiving her Bachelor of Science in Nursing from Georgetown University in 2018, where she also excelled as a Division 1 field hockey athlete. An East Coast native, Megan relocated to Chicago in 2022 and has enthusiastically embraced the Midwest as her home. Outside of the clinic, Megan enjoys traveling to new places, spending quality time with family and friends, and staying active through regular exercise and a focus on wellness.
Whether addressing complex skin concerns or guiding patients through preventative skincare routines, Megan strives to create a supportive, trustworthy environment where every patient feels seen, heard, and cared for.
Specialties: Adolescent and adult acne, general dermatology
Mari De La Roca
SKINCARE SPECIALIST
Mari De La Roca is a skilled licensed esthetician with 16 years of experience in the aesthetic industry and over 24 years of clinical work and assisting in surgical, general, and cosmetic dermatology. Graduating from the Naperville Skin Institute, Mari is committed to helping her patients achieve their skincare goals through personalized treatments and comprehensive product knowledge.
Mari’s expertise encompasses a wide range of advanced aesthetic techniques, including microneedling, chemical peels, body contouring, tissue tightening, skin rejuvenation treatments, dermaplaning, medical grade facials, and microdermabrasion. She takes pride in customizing each treatment to address the unique needs of her patients, ensuring they feel comfortable and empowered in their skin.
Her extensive knowledge of skincare products allows Mari to recommend the best solutions for every skin type and concern, making her an invaluable resource for patients seeking effective skincare routines. She holds numerous certifications, including Basic Life Support, Oncology in Professional Skin Care, Aviclear, SkinCeuticals Chemical Peels, Ulthera, SylfirmX, and ongoing training in CoolSculpting technologies, complemented by her foundational nursing education from Wilbur Wright College.
In her personal time, Mari enjoys dancing, listening to music, and making memories with her family and grandkids. She believes that self-care is essential for well-being and strives to create a warm, inviting atmosphere for her patients. Whether you’re looking for rejuvenating treatments or expert skincare advice, Mari is here to guide you on your journey to radiant skin.
