Pharmacist's Role in the Safe and Effective Use of GLP-1-Based Therapies: A Narrative Review

Abstract

Background The dual GIP/GLP-1 receptor agonist tirzepatide with glucagon-like peptide-1 receptor agonists now include not only reduction of glucose levels but have proved their worth by acting on body weight and heart/kidney benefits. These drugs have shown their efficacy in reducing body weight, heart disease risk, and kidney damage. However, medication safety continues to be an area of concern for the pharmacy because of the nature of the drug absorption through self-injection with stepwise doses increasing. It is, however, expected that in time new safety signals will emerge, and these will need to be monitored in conjunction with known adverse effects. Objective: To describe the role of the pharmacist in the safe and efficient use of GLP-1-based therapeutics, with a focus on Indian practice, and to summarize the pharmacology, formulations, clinical evidence, and safety profile of these treatments. Results: Tirzepatide showed better weight loss than semaglutide at up to -20.2% vs. -13.7% in SURMOUNT-5 and caused a mean weight change of -20.9% after 72 weeks in SURMOUNT-1 versus only -3.1% with placebo. While 1 mg of semaglutide significantly reduced the risk of a composite of kidney events by 24% in the FLOW study, 2.4 mg of semaglutide reduced the occurrence of adverse cardiovascular events by approximately 20% in SELECT. Among the safety issues that pharmacists should be aware of are dose-dependent gastrointestinal effects, gallbladder disease, a possible association with semaglutide and non-arteritized anterior ischemic optic neuropathy (NAION), the risk of procedural aspiration that is still unclear, and administration error with compounded vial products. Certainly pharmacists must keep in mind some major safety issues: Gastrointestinal side effects related to dosage; gallbladder disease; an alleged connection between semaglutide and anterior non-arteritic ischemic optic neuropathy (NAION); uncertainty with procedural aspirations; administration errors of compounded vial products. Conclusion: Pharmacists can assist in bridging the gap between trial efficacy and real-world results by utilizing eligibility screening, titration and injection counseling, error prevention, adherence support, and pharmacovigilance. Controlled research is essential for pharmacist-led interventions especially in India.

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Darpi Patel, Esha Patel, Garvi Patel, S P Srinivas Nayak. Pharmacist's Role in the Safe and Effective Use of GLP-1-Based Therapies: A Narrative Review. ClinSphere Journals. 2026;undefined(undefined). https://doi.org/10.5281/zenodo.23854944

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