Now I really have to marry the princess.

"Sir, it was urgent, that's why I called you! Please don't mind. But, sir, please close the window next time. And..."

Ah Zhong must have misunderstood something. Yang Zhengdao had no intention of explaining, so he listened to Liu Zhong's rambling and quickly walked through the middle courtyard to the front courtyard.

Upon entering the inner hall, one sees a man standing guard by the bed, his face covered in dust and his eyes red.

It was Xi Junmai, whom I had met a month ago in front of the gate of Baojian Temple in Huayuan County.

Before Yang Zhengdao could speak, Xi Junmai bowed deeply, performing a full salute:

"Young Master Yang, please find a way to save my little sister!"

Yang Zhengdao then noticed that a seven or eight-year-old girl was lying on the couch next to Xi Junmai.

Yang Zhengdao rushed forward and saw that the little girl was thin and weak. Her originally delicate face was as pale as paper, her eyes were closed, her small mouth was pursed, and she was completely bloodless.

Suddenly she coughed, and her whole body convulsed violently, as if she were coughing up her internal organs.

Yang Zhengdao hurriedly reached out and touched the little girl's forehead, which was burning hot.

No wonder Ah-chung went to the bedroom to call him; the little girl looked to be in very bad shape.

He turned his head and asked urgently, "Why is your sister like this?"

After listening to Xi Junmai's explanation, Yang Zhengdao finally understood the whole story.

Last year, Xi Junmai's parents passed away one after another, leaving only him and his younger sister, Xi Youniang.

He had used up the hundred coins Yang Zhengdao had given him at Baojian Temple to buy medicine, but Xi Youniang's condition not only did not improve, but worsened day by day.

Xi Junmai had already searched all the pharmacies in Huayuan County with Xi Youniang. When he was desperate, he remembered the note that Yang Zhengdao had left him.

And just as the agreed-upon one-month deadline arrived, he brought Xi Youniang to the address specified in the agreement.

After Xi Junmai finished speaking, he bowed deeply again. When he stood up, his eyes were filled with tears, and his voice choked with emotion: "If my lord can save my sister, I am willing..."

"Don't speak, Mr. Xi!" Yang Zhengdao interrupted Xi Junmai. "Saving patients is like putting out a fire; I will do my best to help."

Although college students have more flexibility in their bottom line, they would never do anything to take advantage of someone's kindness in this situation.

Moreover, judging from the symptoms and Xi Junmai's description, Xi Youniang most likely has pneumonia caused by a cold.

If my guess is correct, then this homemade penicillin treatment could be effective, and might even be able to cure the disease.

Moreover, after he handed over the method of making penicillin using traditional methods to the Imperial Pharmacy, the Imperial Pharmacy should have kept penicillin culture medium in stock at all times.

However, the last time I treated Li Yuan was for a carbuncle, and the treatment was done by applying the poultice to the wound. But to treat this pneumonia, I'm afraid I'll need to take it orally.

As for injections and IV drips!?

Don't even think about it; even if you manage to get the disinfectant alcohol, you still won't be able to get the syringe.

But what dosage should be taken orally? Are there any risks?

Thinking about this, Yang Zhengdao frowned, filled with regret.

Before leaving Chang'an, he hesitated repeatedly but ultimately did not suggest to the Imperial Pharmacy that death row inmates be used for internal drug experiments.

Looking back now, it really was a momentary lapse of judgment, a case of being too soft-hearted.

At this moment, Yang Zhengdao felt anxious when he heard Xi Youniang coughing again.

The only solution now is to split our forces into two groups.

Send Liu Zhong to the pharmacy in the East Market to invite a doctor to come and examine him again to confirm the diagnosis.

He then went to the Imperial Pharmacy to consult with He Guanzhong, the Imperial Pharmacy Attendant, before making any further plans.

Yang Zhengdao, having strained his arm, was led by Aba, with Tan Feng and Su Hongyi following, as they headed to the Imperial Pharmacy in the capital.

On the way, Yang Zhengdao's right eyelid twitched a few times.

But he couldn't remember which eyelid twitching meant good fortune and which meant misfortune, so he didn't pay much attention to it.

Using their official badges as imperial physicians, Yang Zhengdao and his companions were able to enter the imperial city and arrive at the Imperial Pharmacy.

The physician at the Imperial Pharmacy naturally recognized Yang Zhengdao, the young man whom even the Immortal Sun valued, and led him inside.

Ho Kwan-chung happened to be in the office, reviewing past medical records.

After Sun Shenxian twice went to the palace to offer his advice, the old man dusted himself off and went into the mountains. The difficult task of advocating against marriage between close relatives, which offended many people, fell to the Imperial Pharmacy.

When He Guanzhong saw Yang Zhengdao enter, he put down the bamboo slips he was holding and said with a smile, "Young Master Yang, what brings you here today?"

Yang Zhengdao, suppressing his aches and pains, clasped his hands in a respectful bow: "Lord He, I have come to your door today for two reasons: first, to seek your guidance, and second, to request medicine. I hope you will assist me."

"Oh?" Ho Koon-chung raised an eyebrow. "Tell me more."

"There is a young child, about seven or eight years old, who has been coughing for more than a month due to a cold, and now has a persistent high fever. I dare to guess that it is a lung abscess. I think that the penicillin liquid should be able to treat the symptoms, but I have no idea how to administer it internally."

"Internal use!?"

Penicillin can certainly be taken orally, but to convince He Fengyu immediately, it's necessary to use ancient sources.

Yang Zhengdao nodded emphatically: "There is indeed a record in the miscellaneous books of the Later Han Dynasty that it can be taken internally, but how to take it internally is only mentioned in passing."

"I see..." Ho Kwan-chung stroked his beard and pondered, "Master Sun said that the penicillin liquid secretly conforms to the principle of using poison to fight poison, and it is harmless when applied externally. However, if it is taken internally, it must be used with extreme caution."

"I am aware of the danger. However, the child is already terminally ill, and the political responsibility rests with someone else; I can only do my best."

Seeing that He Fengyu was still deep in thought, Yang Zhengdao decided to propose a method for future clinical trials to see if it was feasible.

He continued, "From a political perspective, since this is a case of fighting poison with poison, too little will be ineffective, while too much will leave harmful residues. Comparing the two evils, we should choose the lesser one, or perhaps gradually increase the dosage to observe its effect."

Upon hearing this, Ho Kwan-chung nodded and smiled, "Yes, when faced with two evils, choose the lesser one! That is the ultimate truth."

He then frowned and tapped the table lightly with his fingertips.

If it can be taken orally, penicillin solution could have even greater uses. However, administering the medicine to a young child for the first time is often inappropriate. And even the slightest mistake could give rise to criticism.

Seeing that He Fengyu had not made a decision for a long time, Yang Zhengdao guessed the concerns in He Fengyu's heart.

Even in the Tang Dynasty, doctor-patient conflicts were not uncommon, and as a court physician, he naturally cherished his reputation.

He then bowed to He Guanzhong.

"I understand Your Excellency's concerns. However, that child is an orphan who lives with his elder brother. Now that he has come to me, I cannot bear to see him suffer. Therefore, I will bear all the consequences of this drug trial myself."

"Test the drug..." Ho Kwan-chung pondered for a moment before making his decision.

This young master Yang is indeed shrewd and perceptive. Since this is a trial of medicine, not a medical consultation, any unexpected events would be normal.

His gaze darkened, and he said solemnly, "In that case, Young Master Yang, you should return first. I will discuss this with my colleagues, and once everything is ready, we will go to your residence to test the medicine on the child."

Having received He Fengyu's promise, Yang Zhengdao felt reassured.

He left the Imperial Pharmacy with a dose of mild tonic medicine, intending to brew it for Xi Youniang when he got back.

The group walked out of the imperial city along the side street in front of the palace.

Just after turning past the Imperial City, and only a few dozen steps away from Yanxi Gate, a strange change suddenly occurred.

"Howl...Screech!"

A piercing neighing of horses broke through the air.

Yang Zhengdao's heart tightened, and he subconsciously looked up, only to see a brown horse galloping towards him with its hooves flying!