Vaporizers were originally intended for medical purposes, in particular for inhalation of herbs and oils for patients with bronchial diseases. Now a huge number of manufacturers and models have divorced. Designed for completely different purposes. When looking for a suitable model for vaporizing medicines and vitamins, only the Volcano Classic or Digit comes to mind. These are not cheap models, but they are the most suitable for your purposes.
For the treatment of lung diseases, inhalation therapy is used, which with a very big stretch can be called "smoking". Nebulizers spray fine particles of the drug, which, when inhaled, enter the lungs. But this happens without heating, since high temperatures can change the chemical structure of the drug, as mentioned in other answers to this question.
There are limitations associated with the resistance of medicinal compounds and vitamins to the temperature at which the smoking liquid evaporates, and many compounds will not be volatile enough or will decompose when heated. But as for the rapid entry into the bloodstream - most likely it will be fast enough, and for some medicinal compounds it may be useful. Surely you can think of something effective for the treatment of respiratory diseases (I’m right now, one might say, I’m experiencing menthol smoking liquid). But this is hardly relevant for vitamins, for them the presence in the body in sufficient quantity is more important, and not some instant effect on it.
At your own peril and risk, you can try, most likely there will be nothing, in the worst case - there will be something bad.
The fact is that the chemical structure of the drug depends on how it will be absorbed ... Some substances will react in the environment of the stomach, for example, and nothing useful will remain of them, and if they remain, they will go to the wrong place, so they dissolve sublingually, are injected, and so on (a lot depends on what). And one cannot be sure that the evaporated substance will be the same in chemical composition. And even if it does, it may not reach the circulatory system (again, if in theory it should get into it) and there, in the lungs, it will remain. And if you don't need it, you don't have to clog your lungs with things that are not intended for them.