A Supplement to the Article "The TCM Treatment Mode of Nasal Drug Delivery"

I previously wrote an article titled "The TCM Treatment Mode of Nasal Drug Delivery." Recently, while studying a Western-pharmacology course, I gained some insights, and today I offer some supplementary notes to that article.

Intranasal drug delivery is a form of inhalation administration. The nasal mucosa is rich in capillaries and can absorb drugs directly. After absorption through the nasal mucosa, a drug can enter the systemic circulation directly and be distributed throughout the body via the arteries. This route is very little affected by the first-pass elimination effect.

Here I should explain the concept of first-pass elimination. First-pass elimination, also called first-pass effect (first pass elimination), refers to the phenomenon in which, after certain drugs are taken orally, they are metabolized by enzymes in the intestinal wall or liver as they pass through, reducing the amount of active drug entering the systemic circulation and thereby weakening the drug's effect.

So, although oral medication is the most common and safest route, its effect is inevitably affected by the first-pass effect, and oral drugs must pass through multiple steps of the systemic circulation, so they act slowly.

Intranasal delivery is almost entirely unaffected by the first-pass effect, so a drug can exert its full effect. Moreover, its onset speed is second only to intravenous administration; it is faster than other common routes such as sublingual, rectal, intramuscular, subcutaneous, oral, and transdermal delivery.

This reasonably explains the rapid onset of the several common disease-treating methods I mentioned in "The TCM Treatment Mode of Nasal Drug Delivery" (such as using Focari japonica for sore throat and inhaling arsenic trioxide for lung cancer).

It further shows that this TCM mode of intranasal drug delivery has high value deserving further research.