Dr. Zeffren has been providing high-quality medical care to his community since 1996. He is a graduate of several prestigious medical institutions: he received his Doctor of Medicine degree from the University of Texas Health Science Center at San Antonio, completed his pediatric internship and residency at Cardinal Glennon Children's Hospital/St. Louis University, and completed a fellowship in Adult and Pediatric Allergy and Immunology at All Children's Hospital/University of South Florida. Dr. Zeffren is also a noted public lecturer, is board-certified by the American Board of Allergy & Immunology and the American Board of Pediatrics, and is an active member in many leading medical organizations, including the American Academy of Allergy, Asthma & Immunology (AAAAI), the American College of Allergy, Asthma, & Immunology (ACAAI),and the Florida Allergy, Asthma & Immunology Society (FAAIS). He is currently on the Executive commitee of FAAIS, and he served as president 2009-2010.