Bought some vitamin D drops (liposomal) that say to take under the tongue. Now it’s surprisingly hard to actually do that. So how much am I missing out if it’s in the general mouth or on top of the tongue?
(I might try doing it in front of the mirror.)
To use the pharmacology vernacular, the route of administration for a medication (or supplement in this case) is a balance of pragmatic and biological considerations. Sublingual administration – aka under the tongue – gives access to a lot of capillaries, meaning the medication is quickly absorbed into the blood, without having to go through the liver and first-pass metabolism, which is what would happen with oral administration (aka swallowing a pill). As a practical matter, sublingual tends to be easier if someone cannot swallow, and because it’s very effective, the dosage can be reduced, which potentially could cost less, maybe.
I’m not a pharmacist, but you may find this video by ChubbyEmu adjacently interesting. It is about the difference in topical (aka on skin) absorption rates around the body, where the same dosage can be safe on one’s arm but hazardous on more delicate skin regions.