Recent retrospective cohort studies showed that use of glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) increased the incident risk of diabetic retinopathy and nonarteritic anterior ischemic optic neuropathy (NAION). Furthermore, it was recently reported that use of GLP-1RAs for more than 6 months increased the risk of neovascular age-related macular degeneration (nAMD) by about twofold, although the association between a gastric inhibitory polypeptide (GIP)/GLP-1 receptor dual agonist (GIP/GLP-1RA) and nAMD is not clearly established. We describe the case of a middle-aged male patient with type 2 diabetes without apparent diabetic retinopathy. Due to poor glycemic control, tirzepatide (a GIP/GLP-1RA) was started instead of sitagliptin (a dipeptidyl peptidase-4 inhibitor). After switching from sitagliptin to tirzepatide, glycemic control rapidly improved, but the patient felt haziness with distortion of the central part of the left eye. A diagnosis of neovascular age-related degeneration (nAMD) was made by ophthalmologists in our hospital. The basis for the possible association of tirzepatide administration with onset of nAMD is unknown. However, clinicians should pay attention to potential visual impairments after achieving acute glycemic control with incretin-related drugs, including tirzepatide.