Semen Pini — the edible kernel of Pinus koraiensis Siebold & Zucc. (Korean pine) and of related Pinus species (family Pinaceae).
Nature and flavour. Sweet, warm. Lung, Liver and Large Intestine systems.
The most harmless-looking entry in the purge category, because it is a nut. The sources record it for dryness-type constipation in the elderly and after illness, for dry cough, and as a nourishing food where the body fluids are described as depleted — the same situations that 郁李仁 and 火麻仁 are recorded for, and for the same reason: oil. It is the one entry in this section where the traditional reading and the nutritional reading genuinely agree, and the honest conclusion is unglamorous. There is no distinctive pharmacology here and no controlled evidence for any of the classical indications; what there is, is a fat- and calorie-dense seed that has been eaten for a very long time, and whose traditional reputation for moistening a dry bowel is consistent with what fat and fibre do.
性味归经。甘，温。归肺、肝、大肠经。
泻下药里看起来最无害的一味，因为它就是一颗坚果。文献记载其用于老人与病后的燥结便秘、干咳，以及古籍所谓津液亏耗时的滋补食物——与郁李仁、火麻仁所记的情形相同，理由也相同：油。它是这一节里传统读法与营养学读法真正一致的一味，而诚实的结论并不动人：这里没有特殊药理，也没有任何对照证据支持其古典主治；有的是一枚高脂高热的种子，被人吃了很久，而它「润燥滑肠」的传统声誉与脂肪、膳食纤维的作用是一致的。
它是坚果，也就有坚果的问题。松子过敏不常见但存在，且可能严重。另有一种松子特有的反应值得知道，以免被误当成更严重的事：松子综合征，俗称「松子口」——食用某些松子后一到三天出现金属味、苦味，有时像哈喇味，可持续数天至两三周。它有自限性，不是过敏，机制尚未明确；最常涉及的种类是那些以通用名从中国售出的松子。许多不知情的人曾被它吓到。此外：种仁几乎全是脂肪，会酸败，酸败的松子应当丢弃而非食用。对幼儿，噎呛是真实风险。还有一条适用于本节所有泻药的告诫同样适用于此：新出现的便秘，或伴体重下降、便血、排便习惯持续改变的便秘，应当去检查。坚果不是诊断。