Multiple myeloma is the second most common hematological malignancy. Ixazomib is the first oral proteasome inhibitor approved in the United States for the management of multiple myeloma who have received at least one prior treatment. The availability of oral chemotherapeutic agents for the management of multiple myeloma has made it easier for patients who do not have to come to the hospital for chemotherapy infusions. However, many barriers are associated with oral chemotherapy, and one of them is a misinterpretation of instruction which can have deleterious effects. In this case report, we present a case of a 69-year-old male with multiple myeloma who accidentally took ixazomib daily for 3 days instead of the weekly regimen and thus coming into the hospital with an overdose. In this report, we focus on the adverse effects associated with ixazomib toxicity and how to manage the adverse reactions. Although there is no antidote available for ixazomib, supportive care is very essential in these patients.