Isotretinoin and Thyroid Dysfunction: A Call for Routine Monitoring

Abstract

Isotretinoin is a widely prescribed medication for severe acne and other dermatological conditions. While effective in managing acne, some of its systemic effects were widely discussed. However, its impact particularly on thyroid function remains underexplored. This narrative review highlights current evidence on the relationship between isotretinoin use and thyroid dysfunction, evaluating the need for routine thyroid function testing to help clinicians assess the risk of thyroid dysfunction in their patients. We searched PubMed, Scopus, and Google Scholar from inception to February 2025. Interpretation was guided by a systematic approach emphasizing study relevance, methodological quality, and recency. Inclusion criteria focused on peer-reviewed research addressing isotretinoin’s impact on thyroid function. Study designs, sample sizes, and risk of bias were critically assessed to maintain objectivity and reliability in synthesizing current evidence. Studies consistently report alterations in thyroid hormone levels during isotretinoin therapy, including elevated thyroid-stimulating hormone (TSH) and decreased free triiodothyronine (FT3) and free thyroxine (FT4) levels. Studies suggest that these changes may be mediated through mechanisms involving thyroid cell apoptosis, immunomodulatory effects, or central regulatory disruptions. Females and individuals undergoing prolonged isotretinoin therapy appear to be at higher risk. These findings highlight the importance of routine thyroid function monitoring in patients on isotretinoin, particularly those with a predisposition to autoimmune disorders or prolonged treatment courses. Further research with larger sample sizes and rigorous methodologies is needed to comprehend the underlying mechanisms and refine clinical guidelines. This review emphasizes on the need for a multidisciplinary approach involving dermatologists and endocrinologists to ensure optimal patient care and safety.