This article explores the pitfalls in using glycated hemoglobin A (HbA1c) as a glycaemic monitoring tool in a patient with alpha-thalassemia intermedia. It includes the methods used for HbA1c measurement, such as charge-based or structure-based, presence of hemoglobin variants, ineffective erythropoiesis, concomitant iron deficiency and peripheral hemolysis. For such cases, the use of blood sugar profiles can be a useful alternative to monitor glycaemic control.