You Wash Your Hands. Can Washing Your Nose Help Fight Covid-19?

Learn an easy technique that scientists are testing in the fight against coronavirus.

Executive summary: Soap is effective in killing the coronavirus. You wash your hands to stay safe. Maybe washing your nose, where the virus lives, is something we should be doing. This essay explores that idea, shows how to do it, and reviews some science behind it.

Credibility info: I am a head and neck surgeon, and I have a degree in physics. My understanding of these topics is above average. I use the techniques described below at least once daily.

The rationale

The CDC recommends hand washing as one good way of protecting yourself from the coronavirus. They recommend plain soap and water! The CDC says to use hand sanitizer if you don’t have access to soap and water! The reason is the same as the reason that you put dishwashing soap in a greasy frying pan: soap breaks apart the grease. The coronavirus’s shell is a “lipid layer,” which is grease. Soap breaks apart the shell of the virus and promptly kills it.

When the virus gains entry into your body, it’s usually through the nose, and the virus lives and replicates in the back of the nose and behind the nose. Why not wash that part of your body with soap, too?!

Interlude: the basics of how to wash your nose

Many people who suffer from sinusitis know that they get some relief by doing “nasal rinses,” which is washing the internal nose with salt water. The salt water is put in a small plastic squeeze bottle. You squeeze the water into one nostril, and the water drains out the other nostril. Take 60 seconds to watch this video from a company that makes a convenient nasal rinse bottle.

I know, it looks bizarre, but the technique is thousands of years old, and it’s not uncomfortable, even the very first time you do it. You can pick up that rinse bottle at any drug store.

Now back to the science

The idea of washing the inside of the nose with soap made so much sense, that researchers at Vanderbilt University began a clinical trial at the National Institutes of Health to see whether washing the nose could provide some benefit to coronavirus patients.

In the clinical trial, the soap is Johnson’s Baby Shampoo, one-half teaspoon, mixed in the plastic nasal rinse bottle. Participants in the trial use the nasal wash the same way you saw in the NeilMed video.

Where does the water go, and how does it get out the other side?!

First, let’s get oriented to this diagram:

This person is looking to the right. You see the nose, lips, and chin. The palate separates your mouth from your nasal cavity. If you press up, with your tongue, on the roof of your mouth, you can feel your palate. The back part of the palate is called the “soft” palate, because it can move, and the very back end of the soft palate is the uvula, the little thingie that hangs down in the middle, when you look in the back of your mouth.

You have two separate sides inside your nose, left side and right side, generally outlined in black in the diagram. Behind the nasal cavity area, outlined in green, is a room where the air from the two nasal sides can mix together — there’s no divider between the two sides back there. Picture the green room as a big closet, with two separate hallways opening into the closet side-by-side.

When you start pouring water in one side of your nose, the water will flow back toward the closet, and start to fill the closet behind the nose. When the water level gets high enough, a bit above the floor of the closet, the water will start to flow back out of the closet, down the hallway that is not dumping the water in, and the water comes out of the other side of your nose.

The “closet” behind the nasal cavities is called the nasopharynx, pronounced “nay-zoh-fair-inks.” In this diagram, I have shaded it in blue.

We think that the virus typically first enters the body through the nose. Further, it is in the nasopharynx, and in the back of the nasal cavities, that the virus is thought to hole up and replicate when you first get infected. That’s why we put the Q-tip in soooo far when you get a coronavirus test: we want to get the Q-tip way back to sample fluid in the nasopharynx.

That’s also why we’re washing this area of your body with soap, in addition to washing your hands.

An improvement on the technique

We want the soapy water to touch all parts of your nasopharynx. So, instead of leaning over the sink as you saw in the video, do your nasal rinses with your head tilted up from a neutral standing position, about ten or fifteen degrees up, as if you’re tilting your head a bit to see something on the ceiling.

Why does tilting up work, you ask? The explanation is nerd heaven, and I’ll give it to you, along with a few other improvements, in the optional-to-read bottom section of this essay.

More on mixing up the washing solution

The NeilMed video talks about using distilled water (cleaner than tap water), and putting NeilMed’s powdered salt preparation into the bottle. Your body’s fluids are salty; the inside of your nose likes it better if your washing solution is salty. Here’s what I do: get a gallon of distilled water and put in eight teaspoons of table salt. Make sure it mixes completely. Use that water for your nasal rinses. If you want to do it one rinse bottle at a time, it’s one-half teaspoon of salt in the rinse bottle.

NeilMed suggests heating the water a bit. Room temperature is about 72 and your body is about 98. I’ve tried heating and not, and I don’t notice much difference. Don’t make the water hot and hurt yourself!

The clinical trial suggests one-half teaspoon of Johnson’s Baby Shampoo for each bottle. That works out to about two pumps of a typical 27-ounce baby shampoo pump dispenser. You can measure it for yourself.

After you pump in the shampoo, put your thumb on the top of the bottle and swirl it around to mix the shampoo in. Get the water swirling like a little tornado. Don’t shake it: you’ll just foam things up. If you swirl for only a couple of seconds, and then hold the bottle up to a light, you’ll see strings of shampoo still swirling and dissolving. You have to swirl for about thirty seconds to get the shampoo to dissolve all the way. (Interestingly, if you heat the water to ninety degrees, the shampoo dissolves in about five seconds.)

At first, I found the baby shampoo a touch irritating. So for a week or so I only used one-quarter teaspoon of shampoo — one pump — instead of the recommended one-half teaspoon. Now it doesn’t bother at all.

More on doing the rinse

You can lean over the sink to wash and not spill a drop, even on your first try. But if you do it with your head tilted back ten degrees, all of the water will run down your shirt. You can do it in the shower, or fold a thick bath towel and push it under your chin and in front of your neck to catch the drain-off.

Don’t squeeze the bottle hard. You don’t need a high flow rate. Just squeeze slowly, and let the chore take longer. That way, you’ll spend more time with the soap solution bathing your tissues.

So what, really, are we trying to accomplish here?

Washing the nose with soap is not guaranteed to do anything. I absolutely can’t say that it will decrease your chances of getting the virus, or decrease the severity of your infection if you do acquire it, although scientists are looking into that right now. For certain, wearing a mask and social distancing are far, far more important than the techniques I’ve described here.

But it’s true that soap is utterly deadly to the virus, and I’m happy to participate in techniques that are easy, inexpensive, risk-free, take almost no time, and make sense given the science that we know. And it gives me one more thing to try while waiting for proven interventions, like a vaccine.

That’s my presentation. For those interested in more details, below you’ll find deeper explanations and small improvements on the nasal rinse technique.

Standard disclaimery stuff: I am not your surgeon; this article is not medical advice. I have no financial stake in companies whose products I mentioned. These techniques are not proven to help. So there.

Okay, nerds, let’s have at it! We’ll start with a little more anatomy.

You’ve seen this diagram before.

The dark purple line is the back end of the nasal cavities, where the separation between the left and right sides ends, and the two hallways open into the closet.

When you pour water into your nose, why doesn’t the water just dump down your throat and make you gag?

Because you elevate your soft palate and uvula to press against the back wall of the nasopharynx, and it seals off the closet, keeping the water up in your nose and nasopharynx. Compare the position of the soft palate in this diagram to the previous one. Here, I’ve elevated the soft palate to seal off the nasopharynx.

Now, why should we tilt our heads back?

Here you are, head tilted down, leaning over the sink to do your nasal wash. You put the plastic bottle spout in your right nostril and start pushing in the water. The water level inside your nose rises to the black line at level “1.” You keep pushing, and the level rises to “2,” but the water doesn’t yet come out the left side of your nose, because the water level has only reached the bottom of the purple line that represents where the two sides of the nose open into the nasopharynx.

You push in more water, the water level rises to “3,” and now the water in the closet has access to the empty side of your nose. You’re leaning over the sink, pushing water into your right nostril; it flows from the right side of your nose, into the bottom of the nasopharynx, then into the left side of your nose, and out your left nostril. Fine. But look at the black line of the water level “3,” and look at the blue of the nasopharynx “closet.” Your soapy water, which is supposed to wash your nose and attack the virus, is touching almost none of the tissue of the nasopharynx.

The water level won’t get any higher in the nasopharynx, because the water is now able to flow out the other side of your nose. I think that’s a problem. The nasopharynx is exactly the area we want to wash! Time for an improvement to the technique.

Even if you perform the wash with your head level, you are still missing the entire upper half of the nasopharynx. Here I’ve drawn the black water level a bit above the bottom of that purple line. When the water gets this high, it can swing around the back divider between the left and right side of the nose, come out the other side, and avoid the upper part of the nasopharynx completely. So let’s do better yet.

Now your head tilted back, only ten degrees. You start pushing water into the right side. The water flows back, fills the lower half of the nasopharynx, and rises to a level just above the bottom of the purple line, where the water can get around to the left side of your nose. But the water doesn’t flow out your left nostril yet. See the front end of my black line, at the white arrow? The water level isn’t high enough to make it all the way to the front of the nostril, where it can drip out. The water level needs to rise further, in order to drip out the left side. Let’s see what happens as you keep pushing in the water and the water level rises.

Now the water level is high enough to make it to the nostril and drip out. And you can see that we have now filled the entire nasopharynx. This is how I do my nasal washes, with my head tilted back about 10–15 degrees.

Further improvement with a couple minor adjustments

Earlier in this essay, I used this diagram to show you the water level when the water starts flowing out the opposite nostril, when your head was tilted down. The nasopharynx is mostly dry. But look how much of the (pink) nasal cavity is drenched in soapy water! I also added a thick brown line in the nasal cavity. That line is the location where the nerves that allow you to smell exit the brain and enter the nose. You already know that the virus interferes with your sense of smell. It can’t be a bad idea to get some soap up there. So save some water in your squeeze bottle to tilt your head down and do a squirt in that position.

The inside of your nose and mouth is lined in soft pink tissue. The bright blue area is the soft pink tissue at the back of the nasopharynx. That’s what we want to touch with the Q-tip during a coronavirus test.

What is that heavy black line? It’s the back of the throat. It’s the pink tissue that you see on the back wall of your throat, behind your tongue. It’s completely continuous with the tissue that lines the back wall of the nasopharynx.

Do you think the virus will grow in the nasopharynx, but one millimeter lower, below the soft palate, it won’t? Of course it will! So let’s wash that black line with soap, too. How do you do that? By gargling! Save some soapy water at the bottom of your squeeze bottle to gargle with. Since you’re gargling with soap, huge bubbles will flow out of your mouth.

Finally, as a reward for reading this far, I shall give you one last minor tip. Povidone-iodine is a brownish-colored antiseptic. It’s what the nurse scrubs your belly with before the surgeon takes out your appendix. It’s deadly to the coronavirus, too.

Researchers at the University of Kentucky are running their own clincal trial, to see whether povidone-iodine, used prophylactically as a nasal spray and gargle, can decrease the chances that people, especially front-line workers, acquire the disease.

You can find the antiseptic many places, such as here. I put six or seven drops into the nasal rinse bottle before I do my rinses.

Wear your masks! And stay safe!