Background: Intravenous immunoglobulin (IVIG), as an expensive medication under a national shortage, has been widely used for the treatment of several autoimmune diseases and immunodeficiency syndromes. Although conducting studies on therapeutic indications of IVIG has increased significantly, a limited number of researches have investigated individualized dosing in terms of the drug, disease state, and some patient-specific factors like obesity. Objective: The objective of the review was to describe the impact of various weight-based dosing regimens on the pharmacokinetics parameters, efficacy, safety, and cost of IVIG and to choose the best dosing approach for obese patients. Methods and Results: Thirteen of the total 128 manuscripts collected, reviewed, and analyzed were found from Scopus, PubMed, and Google scholar. Discussion: The evidence suggests that obesity may have an impact on IVIG pharmacokinetics, safety, and efficacy. Conclusion: The logical approach is to initial the dose based on the ideal or adjusted body weight and then modify the maintenance dose according to the patient's clinical response.