"Doctor, I understand that I have kidney problems, but why does it lead to headaches?"

The patient looked confused. "I get it when you say I have symptoms like dizziness, tinnitus, weakness in the waist and knees, and frequent dreams, but why the headache?

"Moreover, it aches whether it's hot or cold, especially when I'm working or when I'm... intimate. That's what I don't get."

By this time, Du Heng had figured it out and was quite relaxed, so he started to explain patiently, "Think of your body like a car engine. For it to work properly, running long distances or carrying heavy loads, wouldn't you need to maintain it? Wouldn't you need to add engine oil from time to time?"

The man nodded blankly, not sure what Du Heng was getting at, but listened attentively nonetheless.

"Your kidneys are like the car engine. You've worn them out when you were young. They are now lacking the lubrication they need. Every time they have to work, they get stuck, which affects other parts and makes you feel unwell in all sorts of ways."

Speaking slowly, Du Heng let his patient absorb his words. "And kidney water serves as engine oil. Your kidneys, because of lack of maintenance, now produce very little kidney water. Any slight amount produced gets depleted before it can even be used.

"What you need to understand is that kidney water serves a great function: it nourishes the liver and reduces the dryness and heat of liver wood.

"With the dryness and heat of your liver wood, your liver fire tends to flare up. And without kidney water, your kidney fire flares up too.

"The liver fire is the thunder fire, while the kidney fire is the dragon fire. When the two fires meet, they form the dragon thunder fire. It surges upward, causing dizziness, and in severe cases, headaches."

In between his words, he tapped the desk with his right hand and continued, "Heat, cold, fatigue, and especially sexual activities only further weaken your kidneys.

"When the kidney gets overburdened, the little kidney water you have loses its effect, giving rise to the headaches. If you don't get headaches under these circumstances, who would?"

The patient listened, pressing his lips together. It took a good while before he finally spoke, "So, is there any hope for me?"

"It's not too late. You can be cured, but you have to follow my instructions."

"I will, I definitely will!" The patient quickly agreed, as if terrified that Du Heng might change his mind.

Du Heng gave a light laugh, which helped ease the patient's tension. "Your condition is rather difficult to treat. Your lack of kidney water has been too severe, and it's not easy to replenish."

As the patient's face began to pale, Du Heng continued, "But there's a treatment. As long as we greatly replenish the water in your kidneys and add a small amount of fire-tonifying medicine, the water can then control the fire. This will lead the fire back to its source and naturally guide it into the kidney palace.

"Once the fire is nourished by water, the dragon thunder fire will safely reside in the kidneys and not rise upward causing headaches."

While speaking, Du Heng glanced at Doctor Ma, then turned his attention back to the patient. "The medication is not that complex, either. Based on the Six-Ingredient Rehmannia Pill, we add rhizoma ligustici and cinnamon to make an Eight-Ingredient Rehmannia Decoction. After two doses, your headache should go away. After ten doses, your kidney water should be ample.

"Then, we'll change the medication. Another ten to twenty doses will completely eliminate the root cause, and it won't relapse."

Seeing the happy look on the patient's face, Du Heng warned seriously, "But during the course of medication, you must abstain from all forms of sexual activity. Any further damage to the kidneys would be beyond remedy."

The patient kept nodding his head, showing no sign of resistance. He clearly understood the difference between three months of indulgence and decades of comfort.

Du Heng then wrote down the prescription, specifying the doses and how to use them, and gave it to Doctor Ma, his signature duly affixed.

After what had just happened with Qiu Pingzhen, he had become more aware of the need to avoid possible oversights he might have made before.

When the patient happily left with the payment receipt and prescription, Du Heng also prepared to leave. He had to look for Wu Shengnan; the woman had been away from home for three days. 𝐟𝗿𝐞𝚎𝚠𝐞𝚋𝕟𝐨𝚟𝐞𝕝.𝕔𝕠𝚖

However, Doctor Ma, still laden with questions, quickly stopped Du Heng. "Dean, there are a few things I need to clarify."

Helplessly, Du Heng had to sit down again. "Go ahead."

"Dean, could you explain why you chose to use the Eight-Ingredient Rehmannia Decoction? And from what I remember, we should add cassia twig and aconite, not rhizoma ligustici and cinnamon," Doctor Ma asked carefully. He had used the Six-Ingredient Rehmannia Pill before, but never the Eight-Ingredient Rehmannia Decoction.

Du Heng did not look down on Doctor Ma because of his inquiry. The formula was not commonly used, after all.

"Let me answer your first question: why I'm using rhizoma ligustici and cinnamon this time, instead of the more common cassia twig and aconite." Du Heng gave Doctor Ma a smile and adjusted his sitting position to be more comfortable.

"The patient is suffering from a serious deficiency of kidney yin. Cassia twig and aconite, being yang-promoting herbs, are not appropriate at all," Du Heng said, his expression becoming a bit serious. "Cinnamon is an extraordinary herb for guiding the fire back to its meridian, while rhizoma ligustici is an excellent remedy for headaches. It addresses the patient's problem directly.

"Moreover, the Six-Ingredient Decoction is a wonderful remedy for nourishing the essence. Combined with these two herbs, it should take effect immediately, which is why I said the headache would be relieved after two doses."

Doctor Ma had an enlightened expression and quickly noted it down.

Du Heng saw Doctor Ma jotting things down and deliberately slowed his speech. This attitude was exactly what he liked.

In the four months he had been at the Municipal Maternal and Child Health Hospital, he had explained many case studies to the doctors. However, only Doctor Ma had the habit of taking notes. Even the young Li Shuxun never made notes.

"Old prescriptions should not be changed arbitrarily, for they are the product of thousands of years of experience from our ancestors. However, when using these prescriptions, one should not follow them word for word either."