Diabetes is a chronic metabolic disease characterized by elevated blood sugar levels. It can also mean long-term problems with the metabolism of carbohydrates caused by insulin deficiency, which leads to hyperglycemia and glycosuria. Weight gain is a common side effect of insulin therapy and other oral antidiabetic medications for diabetic patients, which can hinder their ability to meet strict glycemic targets and potentially reduce treatment success. Insulin-related weight gain is attributed to anabolic effects, appetite increases, and reduced glycosuria. Insulin therapy has been linked to increased cardiovascular risk and mortality in type 2 diabetes patients, as well as inflammation, atherosclerosis, hypertension, dyslipidemia, heart failure, and arrhythmias. Large-scale evaluations suggest that insulin therapy has a poorer short- and long-term safety profile than other anti-T2D therapies. To treat diabetes, a variety of insulin formulations are available, each acting at a distinct pace. Whether they are long-acting, intermediate-acting, or rapid-acting, there are similar adverse effects to be mindful of. Weight gain, injection site responses, and hypoglycemia (low blood glucose) are common side effects of insulin. Lipodystrophy, or improper fat distribution, and limb edema are uncommon adverse effects of insulin. When it comes to insulin introduction, titration, and follow-up treatment, doctors can manage patients with type 2 diabetes mellitus more effectively by employing simple algorithms. Primary care doctors and other medical professionals can manage patients with type 2 diabetes mellitus more easily by using streamlined insulin introduction and titration protocols.