Windy: Sounds like you did the right thing based on your dosage analysis. Do let us know how you do after a few days compared to your previous experience.

I think there are quite a few medications that should/need to be calibrated based on weight. Why is this not done?

The medical world seems quite aware about being careful about dosage when there are children involved but that does not seem to carry over to adults. Especially older adults.

One size usually does not fit all.