I am on 60 mg. of cymbalta (duloxetine) for ten years. my dr. wants me to take indefinitely. will this cause memory loss if i take for another 20 yrs.?

Depends: Memory loss has been reported as a Cymbalta (duloxetine) side effect though not common. Depending on your health status, other medications you take, family history of memory loss/dementia, you should continue to pay attention to possible memory loss due to Cymbalta (duloxetine) or other causes. Chances are you'll be fine. Good to review your meds and any side effects at regular intervals with all prescribing doctors.

No.: Memory problems are such a remote possibility that it would not be worth your concern. They are not known to develop with long term use. And, your dose is not high. But you should be posing your question to your doctor.