Our Team

Medical Director

David Calderwood, MD graduated from the University of Washington in Seattle in 1981. He completed a 3 year Family Practice Residency program and passed his American Board of Family Medicine in 1984. He worked in hospital emergency departments for 20 years during which time he also passed the American Board of Emergency Medicine exam. In 2004 he left the practice of emergency medicine and began practicing family medicine until 2020. In that year he left office practice and began treating COVID-19 patients and Long COVID patients.

CEO & Clinic Director

Certified Health Coach, Researcher

Oncologist

Dr. “Libby” Lowenthal has proudly called Alabama home since 1993, when she moved to Birmingham to complete her medical oncology training at UAB. For over 15 years, she dedicated herself to providing exceptional oncology care to patients across central Alabama while also managing a farm in Columbiana, where she raised spotted saddle horses, donkeys, and mules.

In 2009, Dr. Libby moved to New Zealand in search of new innovative solutions in healthcare. During her time there, she deepened her expertise in integrative oncology and completed fellowship training in Nutritional and Environmental Medicine as well as Lifestyle Medicine. Dr. Libby spent three years in New Zealand’s public healthcare sector before establishing several integrative oncology practices. She worked closely with radiation oncologists, particularly focusing on genitourinary cancers.

Dr. Libby is committed to combining her extensive knowledge in oncology, nutrition, and lifestyle medicine—whether it’s recovery from cancer or achieving optimal quality and longevity of life.

Medical Doctor
Alice Tzeng, MD spent most of her life in NJ, and graduated college from the New Jersey Institute of Technology.

She received her M.D degree from the University of Medicine and Dentistry - New Jersey Medical School, now part of Rutgers University. Prior to starting her internship and residency, she did a year-long research fellowship with the National Institute on Disability and Rehabilitation Research. Afterwards, she completed a residency program in Physical Medicine and Rehabilitation at Kessler Institute for Rehabilitation and practiced as a board-certified physiatrist in NJ, specializing in evaluating and treating injuries and diseases causing loss of function, disability, and pain. She, her husband, and 3 children moved to Huntsville from NJ in July 2022. Due to the birth of her first child, as well as having a brother-in-law and mother who were diagnosed with cancer, Dr. Alice began seeing the limitations of western medicine and became intrigued with holistic medicine. She became a certified Root Cause Protocol consultant to help those who want to optimize their health by addressing the root causes of disease.

Dr. Alice is currently a medical consultant for her husband's law firm, Citizensoldierlaw.com, which serves the military and veterans, particularly in helping them with getting disability benefits and now joins the Sparrow team and hopes to be a blessing to her patients with her knowledge of both traditional western medicine and holistic medicine.

Family Nurse Practitioner

As a dedicated and compassionate Nurse Practitioner (NP) at Sparrow, I am committed to providing high-quality healthcare services to individuals and families in our community. With a strong background in primary care and a love of holistic wellness, I strive to empower my patients to achieve their health goals and lead fulfilling lives.

My journey in healthcare began in 1992 at Calhoun Community College, where I gained valuable clinical experience and developed a passion for patient-centered care. I continued my education and earned a Bachelor of Science in Nursing and 2 Master degrees (MSN) with the last being a specialization in family practice, further enhancing my clinical skills and knowledge. Lastly, I completed a terminal degree with a Doctorate in Nurse Science from UAH to better understand research and education. As you can see, I love to learn and do not plan to stop anytime soon! I am dedicated to staying current with the latest advancements in healthcare through continuing education and professional development.

At Sparrow, I collaborate with a multidisciplinary team of healthcare professionals to provide comprehensive and personalized care to each patient. My areas of expertise include preventive medicine, chronic disease management, wellness counseling, and health education. I believe in building strong relationships with my patients based on trust, empathy, and open communication.

When I am not working, I travel with my husband to visit our 6 children and 2 grandchildren, garden, read, and attend my favorite bible studies. We also love kayaking, hiking, and eating. 

I am honored to be part of the Sparrow team and look forward to making a positive impact on the health and well-being of our patients.

Nurse Practitioner

I am passionate about health and wellness, both personally and professionally. I see my patients as a whole- mind, body, and spirit. I have over 11 years of experience in healthcare. I graduated from the University of Alabama with my BSN, then from the University of South Alabama with my MSN. While I have spent most of my healthcare career in ICU and Hospitalist roles, I am committed to keeping my patients out of the hospital. Improving my patient’s quality of life through the lens of holistic care brings me such joy!I was born and raised in Birmingham, where I currently live with my husband and 3 children. During my free time, haha just kidding what parents have free time, I homeschool my kids. Instilling a love of learning, an appreciation for nature, and preserving a wild and free childhood is important. Rapid fire of things I enjoy- hiking, spending time outdoors with family, walking with neighbors/friends, anything stars and space related, living room dance parties, sunsets, being barefoot, gardening, homemade anything, trail running, and movie quoting.My family is blessed to attend a local church where I have the privilege to serve with kid’s ministry. Jesus Christ is the savior of my life. May my life and gifts bring all the glory to Him.I am honored to be part of the Sparrow team. I look forward to serving our community through compassionate and comprehensive care. I am devoted to the ongoing journey of expanding my knowledge for the betterment of our community and patients.

Family Nurse Practioner

I am a Family Nurse Practitioner passionate about health, wellness, and helping others live their best lives. I earned my Bachelor of Science in Nursing from the University of Alabama at Birmingham and my Master of Science in Nursing from Samford University. My years of experience in primary care, women’s health, and the NICU give me a broad perspective on patient care at every stage of life.What drives me most is taking a holistic, individualized approach to care, helping patients uncover the root causes of their health concerns and empowering them to reach their goals. My expertise includes preventative care, chronic disease management, autoimmune conditions, women’s health, nutrition, and overall wellness. My faith in Jesus is the foundation of my life and practice. Serving my patients and community with all my heart is not just my career—it is my calling. I am grateful to get to know and walk alongside patients on their journey toward health and wellness, trusting wisdom and guidance from Jesus! HE is the ultimate Healer! Outside of work, I enjoy spending time with my two children, exercising, traveling, cooking, embroidery, ministry work, and cherishing moments with family and friends. I am committed to continually learning and growing so I can provide the best care possible for my patients. I am truly honored to be part of the Sparrow team, where I live out this mission every day.

Family Nurse Practitioner

Lindsay has been practicing as a nurse practitioner since 2015. She earned her Bachelor of Science in Nursing from Jacksonville State University in 2010 and completed her Master of Science in Nursing at Troy University in 2015.

Before becoming a nurse practitioner, Lindsay spent five years caring for critically ill patients in the ICU, where she developed strong clinical skills and a deep compassion for individuals and families facing serious illness. Those early experiences continue to shape her approach to patient care today.

As a nurse practitioner, Lindsay has worked in pulmonary medicine, with the majority of her experience focused in primary care and vascular medicine. She is committed to providing thorough, patient centered care that supports physical, emotional, and spiritual well being.

Lindsay believes God called her into healthcare and considers it a profound privilege to serve others. She regularly prays that God will use and guide her in every patient encounter, granting wisdom, discernment, and compassion so she may care for each individual with excellence and love. She views every appointment as an opportunity to reflect Christ’s heart through thoughtful, personalized care.

Outside of her professional life, Lindsay has been blessed with 16 wonderful years of marriage to her husband. Together they are the proud parents of two active sons who keep them busy with baseball, football, basketball, and fishing.

Family Nurse Practitioner

Jamie is a Certified Registered Nurse Practitioner with a Bachelor of Science in Nursing from Ohio University and a Master of Science in Nursing from Troy University.

Before becoming a nurse practitioner, Jamie built her clinical foundation in some of nursing's most demanding environments — acute care float pool settings ranging from medical-surgical to trauma, as well as hematology and oncology. That breadth of experience gave her both the clinical precision and the compassionate perspective that define her approach to patient care today.

With over 14 years of nursing experience across a wide range of clinical settings, I am deeply passionate about helping others achieve true wellness through holistic, functional, and natural approaches to health. My journey in healthcare has shaped my belief in treating the whole person—mind, body, and spirit—while empowering individuals to take an active role in their healing.

Outside of my professional life, I am a devoted wife and proud mother of two, and my family is the heart of everything I do. My faith in God guides both my personal life and my approach to care, grounding me in compassion, purpose, and a heart for serving others. I also have a strong passion for fitness and working out, recognizing the vital role movement plays in overall health and longevity. In my free time, I enjoy being outdoors, renovating our home, and refurbishing antique furniture—finding joy in restoring beauty and purpose, much like I strive to do in the lives of those I care for.

Registered Nurse & Infusion Specialist

Ginger is an exceptional infusion professional with over 20 years of experience in the medical field. Ginger
brings a wealth of knowledge and a compassionate approach to patient care that is truly unmatched.

Ginger's impressive background includes 7 years in medical-surgical and hematology-oncology, 12 years in emergency medicine, and 7 years as a PICC/Vascular Access Provider. Most recently, she has spent 5 years at McMinn Clinic, specializing in advanced nutraceuticals, functional infusions, and heavy metal toxicant infusions. Her certifications speak to her commitment to staying up-to-date with the latest advancements in her field.

But it's not just Ginger's expertise that sets her apart—it's her unwavering belief in personalized care and treating each patient as a unique individual. She wholeheartedly embraces a blend of functional, Eastern, and allopathic modalities, always striving to provide the best possible treatment for those under her care but above all, FIRST DO NO HARM

Registered Nurse

Neely is a compassionate registered nurse with a Bachelor of Science in Nursing from the University of North Alabama. She began her nursing career in the fast-paced environment of the neonatal intensive care unit, where she developed a deep commitment to patient-centered care and a holistic approach to healing.After several impactful years in the NICU, Neely followed a calling to serve on staff at her local church, where she spent a decade supporting the emotional and spiritual well-being of her community. This season of service deepened her passion for whole-person care—tending not just to the body, but also to the mind and spirit.Now back in clinical practice, she brings a unique blend of medical expertise and spiritual insight to her role, helping patients find balance and wellness in every aspect of life.Outside of work, Neely enjoys long walks and hikes with her two beloved dogs, sharing coffee and conversation with friends, and studying the Bible with her women’s small groups. She is happily married to her college sweetheart and is the proud mom of two grown children.

Patient Care Coordinator

Samford Health Sciences Graduate, Certified Emotion Code Practitioner

Chief Marketing Officer