在非緊急情況下，給予胰島素的首選途徑為何？

胰島素（Insulin）是一種蛋白質激素，若經由口服進入胃部會被胃酸與消化酶分解而失效。皮下注射（Subcutaneous）能提供穩定的吸收率，適合長期糖尿病管理。靜脈注射（Intravenous）雖作用最快，但因半衰期短且風險高，僅限於急性高血糖危象（如糖尿病酮酸中毒 DKA）。肌肉注射吸收太快，且會造成不必要的組織損傷與疼痛。

Insulin is a protein hormone; if taken orally it would be broken down by gastric acid and digestive enzymes. Subcutaneous injection provides steady absorption and is suitable for long-term diabetes management. Intravenous administration acts most rapidly but, because of its short half-life and high risk, is reserved for acute hyperglycemic crises such as diabetic ketoacidosis (DKA). Intramuscular injection is absorbed too quickly and causes unnecessary tissue trauma and pain.