Nonadherence to prescribed medications is a significant issue across many medical specialties and human conditions. Nonadherence affects individuals with chronic diseases like cardiovascular disease, diabetes, hypertension, psychiatric disorders, and respiratory conditions, as well as in more acute conditions. Nonadherence can lead to treatment delays or discontinuation, potentially impacting outcomes, but the challenge of medication adherence spans a wide variety of diseases and treatment settings. Factors influencing nonadherence are complex, including psychological, social, financial, and system-level barriers, which apply to numerous medical specialties. Historically, physicians often had to rely on suspicion and guesswork to identify nonadherence or factors contributing to reduced treatment efficacy and delayed or failed outcomes. This uncertainty often left physicians feeling limited in their ability to provide optimal care and effectively apply diagnostic strategies. Fortunately, today, there are various tools available across medical specialties that significantly reduce the uncertainty surrounding nonadherence and its contributing factors. These tools, while widely available, are sometimes underutilized or less well-known. The purpose of this paper is to serve as both a reminder and an introduction to these tools, encouraging healthcare providers to actively and practically employ them for more accurate patient and treatment assessment. This strategy ultimately supports physicians in their commitment to providing each patient with the best possible care and personalized support, as well as improving physician job satisfaction and reducing overall healthcare costs.