Generally, the ingredients in Gluco Extend are considered safe when taken as directed. However, side effects can occur, especially if you have sensitivities to any of the ingredients or if you are on medications that affect blood sugar. Common side effects may include mild digestive discomfort or low blood sugar (hypoglycemia) in individuals who are already on diabetes medication. As with any supplement, it's important to consult a healthcare professional before starting Gluco Extend, especially if you have diabetes, are pregnant, or are taking other medications.