It is prescribed for many reasons, high blood pressure, anxiety, cluster headaches,
and tremors. It does have a break-in period,
and low energy, and sleepiness are part of the break-in period, which can take up to 6 weeks. I have never heard of it being prescribed for depression, but rather anxiety. I think she needs to return to her doctor to re-evaluate this medication. She is in a rough situation, to be 75 and having to care for your father, I can understand her depression.