大凡煎药退热。药须要清利。不可用火太猛。火势蒸炎。水数易干。须是火势得中。扇之恐灰土泥飞入药中。服之
反为害也。要当家人监视。不可专付婢仆也。
凡眼药率多凉剂。必于食后服之。或者徒泥其说。往往食未下咽。药即入口。是致食气与药气冲搏。酿积于脾胃之
上。不谓药无其效。且使脾家受冷。旋至虚弱。须当食歇片时。候胸隔稍宽。然后随意服之。尤贵冷热得所。大热则非
肝肺所宜。大冷则脾肾停积不化。宜自斟酌耳。
凡点眼之药。多用脑、麝之类。通入关窍毛孔。易至引惹风邪。点眼之时。宜向密室端坐。然后用铜箸点少许药放
入眼内。点毕。以两手对按鱼尾二穴。次合眼良久。候血脉稍定。渐渐放开。若是夜卧用药。则又不拘此法也。或向当
风去处。或者点罢即开。则风邪乘入。血脉涩滞难散。疾势愈切。切须留意。
凡眼初患之时。眼前多见蝇飞花发。垂 。薄烟轻雾。渐渐加重。不痛不痒。渐渐失明。眼与不患眼相似。且不辨
人物。惟睹三光。患者不觉。先从一眼先患。向后相牵俱损。此是脑脂流下。肝风上冲。玉翳青白。瞳人端正。阳看则
小。阴看则大。其眼须针。然后服药。治用防风散、羚羊角饮子。
诗曰∶
翳中再好是团圆 一点油如水上盘 阳里看时应自小 阴中见则又还宽
金针一拨云飞去 朗日舒光五月天 不是医人夸巧妙 万两黄金永不传
防风散
茺蔚子 防风 桔梗 五味子 知母（各二两） 黑参 川大黄 细辛 芒硝 车前子 黄芩（各一两）
上捣罗为末。以水一盏。散一钱。煎至五分。去渣温服。食后。
羚羊角饮子
羚羊角（三两） 知母 细辛 车前子 人参 黄芩（各二两） 防风（二两半）
上捣罗为末。以水一盏。散一钱。煎至五分。夜餐后。去渣温食之。
Generally, when decocting medicine to reduce fever, the herbs must be clear and unobstructed. The fire should not be too fierce; if the fire is too strong, it will cause steaming and inflammation, and the water volume will easily dry up. The fire intensity must be moderate. Fanning may risk ash or soil flying into the medicinal liquid, which would be harmful if ingested. It is necessary for a family member to supervise the process; one should not solely entrust it to maids or servants.
Eye medicines are mostly cooling preparations and must be taken after meals. Some people rigidly adhere to this rule, often taking the medicine before the food has even been swallowed. This causes the qi of food and the qi of medicine to clash and collide, accumulating above the spleen and stomach. Not only does this impair the efficacy of the medicine, but it also chills the spleen, leading to subsequent weakness. One should wait until some time has passed since eating, until the chest and diaphragm feel somewhat relaxed, and then take the medicine as appropriate. It is especially important that the temperature of the medicine be suitable. If it is too hot, it is unsuitable for the liver and lungs; if it is too cold, it causes stagnation and failure to transform in the spleen and kidneys. Therefore, one should exercise personal judgment.
Medicines used for eye instillation often contain musk (Moschus) and borneol (Borneolum Syntheticum), which can penetrate through the orifices and pores, easily inviting wind pathogens. When instilling eye drops, one should sit upright in a sealed room, then use a chopstick made of copper to place a small amount of medicine into the eye. After instillation, press the Tongziliao (BL1, Pupil Distal Point) acupoints on both sides with the hands, then close the eyes for a long while. Wait until the blood vessels stabilize, then gradually open them. If using medicine while lying down at night, these rules do not strictly apply. However, if one faces a drafty area or opens the eyes immediately after instillation, wind pathogens may enter, causing blood stasis that is difficult to dissipate, and the disease condition will worsen. One must pay close attention to this.
When an eye disease first occurs, the patient often sees floating spots like flies or flowers, curtains hanging down, thin smoke, or light fog. These symptoms gradually worsen without pain or itching, leading to gradual loss of vision. The affected eye appears similar to the healthy eye. The patient cannot distinguish people or objects, seeing only the "three lights" (sun, moon, stars). The patient is unaware of the onset. It usually starts in one eye and later affects both. This is caused by brain fat flowing downward and liver wind rushing upward. The corneal opacity (Yu Yi) is blue-white, and the pupil is regular in shape. Under sunlight, the pupil constricts; in dim light, it dilates. This condition requires acupuncture treatment followed by herbal medicine. The treatments used are Fangfeng San (Saposhnikovia Powder) and Lingyangjiao Yinzi (Antelope Horn Decoction).
Poem:
Among opacities, the best type is round and complete,
Like a drop of oil floating on water.
Under sunlight, it appears smaller,
In darkness, it appears wider.
With a golden needle, the clouds are swept away,
Revealing bright light like a May sky.
It is not the physician boasting of skill,
But a secret worth ten thousand taels of gold, never transmitted.
Fangfeng San (Saposhnikovia Powder)
Chongweizi (Ecliptae Fructus), Fangfeng (Saposhnikoviae Radix), Jiegeng (Platycodonis Radix), Wuweizi (Schisandrae Fructus), Zhimu (Anemarrhenae Rhizoma) (each 2 liang); Heishen (Black Ginseng), Chuan Dahuang (Rhei Radix et Rhizoma), Xixin (Asari Radix et Rhizoma), Mangxiao (Natrii Sulfas), Cheqianzi (Plantaginis Semen), Huangqin (Scutellariae Radix) (each 1 liang).
Pulverize and sieve the above ingredients. Take 1 qian of the powder with 1 cup of water, decoct until 0.5 cup remains, remove the dregs, and take warm. Administer after meals.
Lingyangjiao Yinzi (Antelope Horn Decoction)
Lingyangjiao (Saigae Tataricae Cornu) (3 liang); Zhimu (Anemarrhenae Rhizoma), Xixin (Asari Radix et Rhizoma), Cheqianzi (Plantaginis Semen), Renshen (Ginseng Radix), Huangqin (Scutellariae Radix) (each 2 liang); Fangfeng (Saposhnikoviae Radix) (2.5 liang).
Pulverize and sieve the above ingredients. Take 1 qian of the powder with 1 cup of water, decoct until 0.5 cup remains. Remove the dregs and take warm after dinner.