Baby meds

My daughter is teething and baby pain relief is a life saver. To add on to having two teeth come in at the exact same time at the exact same rate she has surgery in exactly a week. We have two medicine droppers but I just gave our good one to a neighbor and told her to keep it bc we have two of them. The other one has almost all the numbers smeared off except the smallest dose which is what my daughter takes. Obviously it's not that inconvenient now but it will be in the future.

Is there a way to prevent this?? Or a dropper that doesn't do this?? I'm pretty sure this only happened bc my fiance scrubbed it with really hot water cause I've never had this problem before he washed it.

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