

Thomas P. Connelly, D.D.S. Headshot

Why We Take Medicines Under Our Tongue

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As a NYC Cosmetic Dentist, I get all manner of questions from patients. Most of them are garden variety tooth and mouth questions, but every now and again, I get a good one that I file away to post here.

The other day, I got such a question that became the topic for this week's post: just why do we take certain medicines sublingually (under the tongue)?

It made me pause for a second, because it's not something we think about all that often. But yes, we DO take certain medicines under our tongue. And I know the one obvious answer off the top of my head -- "because then the medicine gets absorbed by the body faster" -- but then that brought up more questions like "why?" (they hit the bloodstream faster?) And is the medicine then more effective? So I figured this would make an interesting topic to discuss here.

Indeed, almost everyone knows the surface answer -- "the medicine is absorbed by the body faster." But why is that? Well, I'll tell you ... essentially, when a medicine is placed under your tongue, it diffuses through the mucous membranes beneath your tongue. And because of the plethora of capillaries there, the medicine has a fairly direct route into your bloodstream. This results in the medicine working faster, and oftentimes, better (which you'll see why in a minute.)

Ok, you say, but WHY does it work faster?

Good question -- here's the answer: When you swallow a pill, it must go through your entire gastrointestinal tract. This means the stomach (with acid and bile), the intestines (where most absorption takes place) and then off to the liver, for some more filtering. And THEN it's delivered to where it's needed.

Truthfully, it's the long way, when you think about it. Going under the tongue bypasses this entire route, and delivers the medication right to the bloodstream. No waiting, no roadblocks -- just right into the blood and off to do its job.

In addition to the speed, the medicine delivered sublingually is usually more potent, and (in general terms) needs less medication to do the job it's intended to do (you may have heard stories about people cutting pills in half, then taking them under the tongue, to produce the same effect as swallowing one pill). The reason for this increased effect is the digestive tract is incredible harsh. And it's meant to be -- it's how food is broken down, and the nutrients get stripped out, while the waste goes ... well, you know.

This process, without question, will weaken most medication. So that's why some people will "cut" pills or otherwise take them under the tongue (however, I do not recommend you do this on your own without professional guidance -- in other words, ask your doctor before you start cutting your pills in half, no matter what anyone else has told you).

That said, sublingual delivery is actually preferred for certain medications (like cardiovascular drugs, steroids, etc), and recently, vitamins and minerals (in fact, I even came across some spray vitamins while reading about this topic, which I found somewhat humorous at first, but then thought "hey, why NOT?" -- I mean, some vitamins are literal horse pills in size, so I guess it just makes sense).

Expanding on that last statement, there are also plenty of people who have a hard time swallowing pills (or perhaps they have a throat condition that makes swallowing anything extremely difficult). For these people, taking medication sublingually (if possible) is definitely an advantage.

So far, it seems sublingual is very advantageous -- it's faster, the medicine is usually more potent, so it brings up another question: Why don't more (or all) medicines go this route? Well, the first answer is a pill is WAY easier to take then putting something under your tongue and holding it there for 10 minutes or so.

But the "medical" answer is that absorption by your body is far more controlled in solid pill form. With sublingual delivery, you may accidentally swallow some, leading to a somewhat erratic absorption rate (see merckmanuals link below), which could produce unwanted effects. In medication, "dosage" is typically very important (that goes without saying, really). And with a solid pill, there's little to no question in terms of how much is in the pill, and how much is meant to be absorbed.

This is why (and it's very important that I stress this) that you ask your doctor before taking anything sublingually that wasn't "meant" to be. Your doctor may give his or her blessing and say it's fine, and they may not. And if it's not good that you cut your pills, perhaps he or she can prescribe a sublingual form, if one exists.

Until next time, keep smiling!

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