药品的“有效期”是指某药品在规定的贮存条件下,能够保持质量的期限。在目前使用的药品中,相当一部分规定有有效期,如抗菌素、生化制剂等。这些药品由于它们本身不稳定和外界条件(温度、光线、水分、空气等)以及包装的影响,在贮存过程中就会逐渐发生变质、失效等情况。通过长期生产实践和科学实验,逐步掌握了这些药品变质、失效的规律,从而规定了在一定贮存条件下的有效期限。我国有关部门对有效期曾有统一规定,药厂生产的药品制造日期(或出厂日期)应与批号对口, The term “expiration date” of a drug refers to the period during which a drug can maintain its quality under the specified storage conditions. In the current use of drugs, a considerable part of the provisions have a valid period, such as antibiotics, biochemicals and so on. Due to their inherent instability and external conditions (temperature, light, moisture, air, etc.) and the effects of packaging, these drugs will gradually deteriorate and fail during storage. Through long-term production practices and scientific experiments, the law of deterioration and failure of these drugs has been gradually grasped, and the effective period under certain storage conditions has been stipulated. Relevant departments in China once had uniform regulations on the validity period, and the date of manufacture (or date of manufacture) of the pharmaceuticals produced by the pharmaceutical factory should be matched with the batch number.