Low blood sugar may cause blindness. Symptoms and signs of hypoglycemia can be divided into two main categories: autonomic arousal symptoms and neurologic glucose deficiency symptoms. Autonomic excitatory symptoms include catecholamine-mediated adrenergic symptoms such as palpitations, tremors, and anxiety, and acetylcholine-mediated cholinergic signs such as pallor, sweating, hunger, and sensory abnormalities. Neurologic glucose deficiency symptoms are a consequence of neuronal glucose depletion in the central nervous system, and symptoms include mental behavioral abnormalities, convulsions, and altered consciousness, ranging from lethargy and confusion in mild cases to coma in severe cases. Other symptoms may include blurred vision, weakness, sleepy thoughts and other discomforts. Patients with low blood glucose should pay attention to their own status at any time, and if they are not feeling well, it is recommended that they go to the hospital in a timely manner and follow the doctor’s instructions for treatment to avoid delaying their condition.