What are the basics of how a nasal decongestant spray works?


What are the basics of how a nasal decongestant spray works?

In: 10

It constricts the blood vessels which constricts the nasal passages and also reduces nasal swelling by not allowing as many pro inflammatory cells to “leak out” of the blood vessels. It’s also why they should only be used short term (a couple days) because your blood vessels will end up getting used to the decongestant and will then always swell up without it.

I’ll add for clarity’s sake, some nasal “anti-allergy” sprays work using a hormone that changes the nature of the sinus cavity, which takes time and diligent applications. Not sure where you live, or what the brand names by you are, but things like “Flonase” (Medically “Fluticason”) take weeks to have an effect, don’t grab those for a quick relief hit.

I’ll cover the sympathomimetic sprays. Your body regulates the width of your blood vessels all the time. If you are in a stressful situation the blood vessels in your muscles will widen, increasing blood flow to allow for better performance. This is mediated by receptors in your blood vessels. But in your respiratory system the opposite is happening, blood vessels are constricted if you are in a stressful situation so that the airflow is maximised. Those nasal decongestant sprays use these receptors, which have a different configuration than the ones in the rest of your body. They activate those receptors, thereby constricting those blood vessels, which leads to reduced swelling. But due to homeostasis they will become less susceptible to this kind of activation after repeated use, and the effect will be reduced also. The balance shifts and then the “standard situation” will be shifted towards swelling. This medication is therefor actually pretty bad. It provides short-term relief at the cost of long-term increased swelling, creating dependence on the drug quickly.