The emergence of glucagon-like peptide-1 (GLP1) and GLP1/glucose-dependent insulinotropic polypeptide (GIP) receptor agonists (hereinafter GLP1-RAs, GLP1-GIP-RAs) have transformed obesity treatment. These agents offer substantial weight loss and notable cardiometabolic and other health benefits. Yet, their success relies on long-term adherence and careful management of side effects. Common adverse events - especially gastrointestinal (GI) disturbances - often lead to treatment discontinuation, weight regain and reduced effectiveness. As healthcare providers with multiple patients' interactions, pharmacists provide continuous care throughout the entire treatment journey, from initiation through titration phase and long-term maintenance. The unique position of pharmacists' interactions with patients enables them to address the high rates of non-adherence commonly observed with GLP1 based medications, which often stem from GI side effects, medication complexity, and patient education gaps. Treatment persistence and patient outcomes can be significantly improved through structured, pharmacist-led strategies, including comprehensive patient education, lifestyle modifications, and judicious use of over-the-counter interventions and vitamin/mineral/supplement therapies. Critical emphasis is placed on the pharmacist's role in preventing and managing serious complications associated with rapid weight loss, particularly sarcopenia and nutrient deficiencies, while maintaining vigilance for "red flags" that signal serious complications requiring physician intervention. This manuscript delineates the rationale for pharmacist involvement through the phases of adherence: initiation, titration, persistence, and discontinuation. It provides side-effect incidence and management tables, possible lifestyle and treatment options in each phase, red-flag and referral criteria, strategies to prevent sarcopenia and nutrient deficiency. Implementing these pharmacist-driven interventions can significantly improve tolerability, adherence, and long-term clinical outcomes in obesity pharmacotherapy.
