I just stumbled across this post after doing some research on pill-bottle cotton (I know, I should have checked here first!). So far, I haven't had ......-tongue (thank goodness!), but my sinuses have never been clearer; I get most of mine from Claritin bottles.
Per a good friend who is a pharmacist, all cotton used in pill packaging is supposed to be sterile, so you CAN use it without boiling. Any medicinal dust on the cotton can cause some funky tastes, but if it is safe to take medicinally, it generally should be safe to "vape", and should only last for a few puffs (enough juice to replace the priming of the wick).
Also, you want to make sure it's real cotton, and not a synthetic mixture (again, from my pharmacist source). Real cotton is generally a bit rougher in appearance than unrolled cotton balls and will usually have some lumps or knots in the strands (slightly courser in texture than a cotton ball) because it results in a slightly more bulky packing material than smoother cotton, so they can use less in each bottle. If it's much finer than what you find in an unrolled cotton ball, then you should burn a little to make sure it isn't synthetic; finer cotton isn't typically used as filler because it takes more to form the same amount of packaging bulk (thus costing more $$).
Pill-bottle cotton is all I use, now... my pharmacist buddy saves it for me out of the bulk pill bottles he uses to fill prescriptions, if they come with cotton in them, plus I go through a bottle of Claritin each month.
Cheers and vape-on!
