How much is 1/2 dropperful?

Should be marked: A prescription that gives doses that way should come with a dropper that is marked at 1/2. If it's not, talk to your pharmacist or dr about exactly how much you need.

Lots of sizes!: Droppers come in many sizes. A dropperful is up to the top line, and a 1/2 dropperful is up to the middle line marked on the dropper. Because people get their droppers mixed up, tylenol (acetaminophen) for children now only comes in one liquid concentration. There used to be 2 concentrations and 2 different dropper sizes, which confused some people. Always use the correct dropper that came with the medicine.