This isn't something I've had to deal with calista but it sounds challenging as too much drooling can lead to sores developing as well as well as making it difficult to keep your husband dry and comfortable. You didn't mention what sort of drops were prescribed, but the ones I know of, are scopolamine, (also known as hyoscine), and these are often administered as behind-ear patches too, so it sounds as if this is what you are using, but now in drop form.
And unfortunately they do cause drowsiness and sometimes dizziness too. I guess it means that you can only weigh up which is the more distressing and troublesome, the drooling or the sleepiness. Perhaps you have more control now that you are giving the medication in drop form, inasmuch as you can withdraw a dose once in a while to try to reduce some of the drowsiness.
Sorry I can't suggest any more than this. Maybe other community members will have better solutions.
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