Why do oral-numbing-gels cause you to lose the sense of taste (when applied to the tongue)?



I was applying a numbing oral gel to my mouth to help with a painful cancer sore. I added too much so I got some on my tongue. I found that I was now unable to taste anything. This got me wondering, why does this numbing agent cause my tastebuds to lose their taste-sensing abilities? Is taste based on touch/feel? I always figured that taste wasn’t really based on the feel of a food/object but more of a chemically constructed sense (if that makes sense?). Anyhow, if anyone can explain what’s happening, that would be great to know! 🙂

In: Biology

Most(Probably all, but theres always that one unknown thing that than makes your statement wrong) numbing gels, creams whatever, work by making your nerves stop sending pain to the brain. But depending on what kind of gel(again I only know of those that also do this but theres probably one that doesn’t) you have it can also cause it to stop sending the signals from your taste.

One of the nerves responsible for taste in the anterior 2/3rds of the tongue (chordae tympani) hitch hikes with the nerve responsible for sense (the lingual nerve)(they travel together) so when the numbing gel is applied it inhibits the sodium transmission thus inhibiting sensory and the special sensory (taste) components.
The gel works by blocking nerve conduction, essentially the cells responsible for sending signal temporarily lose the ability to send signals

The short answer is that most topical numbing gels can’t tell the difference between different types of sensory nerves.

It’s a nerve, it’s in the skin/surface membrane. It’s gonna get numbed.

The only difference between pain receptors and taste receptors is the shape of their ends. Otherwise, they function the same way – for comparison, a light bulb and a radio both run on electricity and both turn off if your house loses power, despite doing completely different things. Pain reduction chemicals all do similar things – they turn down the effectiveness of the nerves, which for this comparison is equivalent to reducing the amount of electricity in the house, which will make the light dimmer and the radio quieter.