# Can humans absorb things through the mouth **URL:** \ **Category:** Factual Questions\ **Created:** [April 21, 2007, 8:04pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098 "2007-04-21T20:04:31Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![NinjaChick](https://avatars.discourse-cdn.com/v4/letter/n/71c47a/32.png) [@NinjaChick](https://boards.straightdope.com/u/NinjaChick)\ **Post date:** [April 21, 2007, 8:04pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/1 "2007-04-21T20:04:31Z")
Fairly self-explanatory. The majority of nutrients/vitamins/minerals/etc are absorbed in the first bit of the small intestine, I remember that much of my high school biology. However, I also know that the majority of colds and other contagious diseases spread when a carrier touches, say, a doorknob, then you touch the same doorknob, and then before washing your hands, touch your eyes/nose/mouth. So either we deal with immensely hardy bacteria that takes a swim in your stomach before moving on to your blood, or it’s somehow absorbed through the skin on the inside of your mouth. So, do things get absorbed through the mouth that way? ---
**Author:** ![Zabali\_Clawbane](https://avatars.discourse-cdn.com/v4/letter/z/ecd19e/32.png) [@Zabali\_Clawbane](https://boards.straightdope.com/u/Zabali_Clawbane)\ **Post date:** [April 21, 2007, 8:08pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/2 "2007-04-21T20:08:24Z")
I know there are medicines that you are supposed to let dissolve in the mouth, and others that you are supposed to take care not to let them dissolve in your mouth, because they are meant to absorb over time. ---
**Author:** ![Khadaji](https://avatars.discourse-cdn.com/v4/letter/k/9e8a1a/32.png) [@Khadaji](https://boards.straightdope.com/u/Khadaji)\ **Post date:** [April 21, 2007, 8:13pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/3 "2007-04-21T20:13:50Z")
[QUOTE=NinjaChick] Fairly self-explanatory. The majority of nutrients/vitamins/minerals/etc are absorbed in the first bit of the small intestine, I remember that much of my high school biology. However, I also know that the majority of colds and other contagious diseases spread when a carrier touches, say, a doorknob, then you touch the same doorknob, and then before washing your hands, touch your eyes/nose/mouth. So either we deal with immensely hardy bacteria that takes a swim in your stomach before moving on to your blood, or it’s somehow absorbed through the skin on the inside of your mouth. So, do things get absorbed through the mouth that way? [/QUOTE] I cannot speak for vitamins, but a used to chew tobacco and I can tell you that nicotine is definitely absorbed that way (based on the nicotine high I would get from chewing.) ---
**Author:** ![Gfactor](https://avatars.discourse-cdn.com/v4/letter/g/9de053/32.png) [@Gfactor](https://boards.straightdope.com/u/Gfactor)\ **Post date:** [April 21, 2007, 8:37pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/4 "2007-04-21T20:37:59Z")
> [@](#): > > The delivery of drugs via the mucous membranes lining the oral cavity (i.e., sublingual and buccal), with consideration of both systemic delivery and local therapy, is reviewed in this paper. The structure and composition of the mucosae at different sites in the oral cavity, factors affecting mucosal permeability, penetration enhancement, selection of appropriate experimental systems for studying mucosal permeability, and formulation factors relevant to the design of systems for oral mucosal delivery are discussed. Sublingual delivery gives rapid absorption and good bioavailability for some small permeants, although this site is not well suited to sustained-delivery systems. The buccal mucosa, by comparison, is considerably less permeable, but is probably better suited to the development of sustained-delivery systems. For these reasons, the buccal mucosa may have potential for delivering some of the growing number of peptide drugs, particularly those of low molecular weight, high potency, and/or long bioiogical half-life. Development of safe and effective penetration enhancers will further expand the utility of this route. Local delivery is a relatively poorly studied area; in general, it is governed by many of the same considerations that apply to systemic delivery. [http://www3.interscience.wiley.com/cgi-bin/abstract/113340441/ABSTRACT?CRETRY=1&SRETRY=0](http://www3.interscience.wiley.com/cgi-bin/abstract/113340441/ABSTRACT?CRETRY=1&SRETRY=0) ---
**Author:** ![Nanoda](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Nanoda](https://boards.straightdope.com/u/Nanoda)\ **Post date:** [April 21, 2007, 8:39pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/5 "2007-04-21T20:39:09Z")
I’m certain that many STDs can be transmitted that way… Doesn’t have to be internal though; [dimethylmercury](http://www.chm.bris.ac.uk/motm/dimethylmercury/dmmh.htm) can kill you with minute amounts on seemingly protected skin. And of course, there are all the various ‘patches’ for various reasons. ---
**Author:** ![fifty-six](https://avatars.discourse-cdn.com/v4/letter/f/5daacb/32.png) [@fifty-six](https://boards.straightdope.com/u/fifty-six)\ **Post date:** [April 21, 2007, 8:59pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/6 "2007-04-21T20:59:49Z")
Lsd ---
**Author:** ![Zabali\_Clawbane](https://avatars.discourse-cdn.com/v4/letter/z/ecd19e/32.png) [@Zabali\_Clawbane](https://boards.straightdope.com/u/Zabali_Clawbane)\ **Post date:** [April 21, 2007, 9:08pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/7 "2007-04-21T21:08:01Z")
There is also a caffine gum, which you chew to let the caffine absorp into your bloodstream. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [April 22, 2007, 12:05am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/8 "2007-04-22T00:05:25Z")
Alcohol. Much of the alcohol you drink is absorbed before it ever reaches the intestines. (That’s part of the reason alcohol has such an effect on people.) ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [April 22, 2007, 12:26am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/9 "2007-04-22T00:26:57Z")
I’ve been told that orange juice is a good thing to drink if your blood sugar plummets, as it begins to be absorbed in the mouth. I imagine that _most_ things begin to be absorbed in the mouth. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 22, 2007, 12:54am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/10 "2007-04-22T00:54:47Z")
[QUOTE=Zsofia] I’ve been told that orange juice is a good thing to drink if your blood sugar plummets, as it begins to be absorbed in the mouth. I imagine that _most_ things begin to be absorbed in the mouth. [/QUOTE] **Untrue.** Absorption of sugars thru the mouth is quite miniscule, compared to absorption via the small intestine. Which is why diabetics having low blood sugar reactions should take glucose orally. Glucose tablets or liquid are preferred as it is directly absorbed and goes into action faster than more complex sugars such as sucrose and fructose, which must be metabolized before being used. So, avoid orange juice, apple juice, or any such sugar supplement unless glucoseis unavailable, for treatment of hypoglycemic reactions. From JAMA: [http://jama.ama-assn.org/cgi/content/abstract/240/15/1611](http://jama.ama-assn.org/cgi/content/abstract/240/15/1611) > [@](#): > > Bioactivity of instant glucose. Failure of absorption through oral mucosa > R. R. Gunning and A. J. Garber > > The efficacy of instant glucose as a potential treatment for hypoglycemia was studied in normal volunteers, with therapeutic doses administered in the buccal cavity. 2-Tritiated glucose (50 mu Ci) was homogenized into each dose before use. Mean blood glucose and serum insulin concentrations were unaltered by instant glucose. Glucose absorption was less than 0.05 mg at any time, and total glucose absorbed was less than 0.1 mg. For comparison purposes, volunteers swallowed a dose of instant glucose. Approximately 88% of the dose was absorbed during a 30-minute interval. Blood glucose and insulin levels increased. **Instant glucose appears to be of therapeutic value only if swallowed by fully conscious, hypoglycemic patients. It should not benefit unconscious patients because of its poor absorption through the buccal mucosa.** ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 22, 2007, 1:06am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/11 "2007-04-22T01:06:34Z")
BTW, _tons_ of meds can be absorbed thru the oral mucosa. Nitroglycerine is one of the most common, but there are lots of others. ---
**Author:** ![Zsofia](https://avatars.discourse-cdn.com/v4/letter/z/7bcc69/32.png) [@Zsofia](https://boards.straightdope.com/u/Zsofia)\ **Post date:** [April 22, 2007, 2:04am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/12 "2007-04-22T02:04:53Z")
Whoops - I’d better tell my dad that, as he’s the one who told me - and he’s diabetic! ---
**Author:** ![jjimm](https://avatars.discourse-cdn.com/v4/letter/j/ba8739/32.png) [@jjimm](https://boards.straightdope.com/u/jjimm)\ **Post date:** [April 22, 2007, 2:11am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/13 "2007-04-22T02:11:04Z")
A “linctus” is a medicine designed to be licked. Also, speed and cocaine can be rubbed into the gums for effect. My, er, friend told me. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [April 22, 2007, 2:27am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/14 "2007-04-22T02:27:36Z")
[QUOTE=Zsofia] Whoops - I’d better tell my dad that, as he’s the one who told me - and he’s diabetic! [/QUOTE] I recommend that all my diabetic patients who are on meds which might cause low blood sugar to carry glucose tablets just for this reason, and not to count on candies or juices to be effective. When low glucose is the problem, it should be treated by taking glucose! (or a shot of glucagon, but that’s another story) ---
**Author:** ![CeilingWhacks](https://avatars.discourse-cdn.com/v4/letter/c/8baadc/32.png) [@CeilingWhacks](https://boards.straightdope.com/u/CeilingWhacks)\ **Post date:** [April 22, 2007, 2:50am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/15 "2007-04-22T02:50:01Z")
As a gastric bypass patient, I take sublingual B12 daily. I was told that it is absorbed better via the blood vessels under my tongue than it would be in my shortened intestine. Regarding B12, I believe it’s more absorbably for everyone…gastric bypass patient or not…sublingually than in pill form. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [April 22, 2007, 11:14am UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/16 "2007-04-22T11:14:03Z")
Someone mentioned nitroglycerine - I tried it a while back to see if chest pains were cardiac (they weren’t). The mild headache that is a common side effect of nitro would start in less than a minute! Read somewhere that the typical way of getting a cold was to get the virus on your hands and then rub your eyes, so it would travel down the tear duct into the nose and start breaching the mucous membranes there. But I would like a good cite on this. ---
**Author:** ![gatorman](https://avatars.discourse-cdn.com/v4/letter/g/96bed5/32.png) [@gatorman](https://boards.straightdope.com/u/gatorman)\ **Post date:** [April 22, 2007, 4:56pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/17 "2007-04-22T16:56:52Z")
Absolutely !! The mouth is a HIGHLY vascular environment (lots of blood vessels close to the surface). Nitroglycerin immediately comes to my mind. When you are having angina (or chest pain) and you have a history of Congestive Heart Failure, one of the first things you can do is put a NG tablet underneath the tongue to alleviate the symptons and possibly save your life! ---
**Author:** ![NinjaChick](https://avatars.discourse-cdn.com/v4/letter/n/71c47a/32.png) [@NinjaChick](https://boards.straightdope.com/u/NinjaChick)\ **Post date:** [April 22, 2007, 5:26pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/18 "2007-04-22T17:26:56Z")
Interesting. Thanks for the answers. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [April 22, 2007, 6:28pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/19 "2007-04-22T18:28:29Z")
In any decent sized “health food store” they will sell sublingual B-12. ---
**Author:** ![Doug\_Bowe](https://avatars.discourse-cdn.com/v4/letter/d/df788c/32.png) [@Doug\_Bowe](https://boards.straightdope.com/u/Doug_Bowe)\ **Post date:** [April 22, 2007, 7:03pm UTC](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098/20 "2007-04-22T19:03:47Z")
[QUOTE=CeilingWhacks] As a gastric bypass patient, I take sublingual B12 daily. I was told that it is absorbed better via the blood vessels under my tongue than it would be in my shortened intestine. Regarding B12, I believe it’s more absorbably for everyone…gastric bypass patient or not…sublingually than in pill form. [/QUOTE] Another GB patient checking in. \* I was told\* that the base of the stomach just where the small intestine starts is the only part of the gastric system that can absorb B12. If you’ve had ruex-en-Y surgery you no longer have that as part of your system. And that’s why we need to a) get a monthly B12 shot or b) take the sublingual B12 daily. [Next page](https://boards.straightdope.com/t/can-humans-absorb-things-through-the-mouth/401098.md?page=2)