How long will I need to be treated for my prostate enlargement?

If BPH = lifetime. If the enlargement is from an infection, then treatment only for a short time. But (as in most cases) if the BPH (benign prostatic hyperplasia) is the cause, then you'll need treatment for a lifetime (or as long as you want the benefits that meds give you). That's why many people choose surgery -- it's more invasive than medications, but is much more durable.