I think a full review of your medicines could be really useful. Maybe the doc prescribing for you doesn't know about your extreme sleepiness. If possible, try getting off any sort of depressant/tranquilizer type medicine that would slow you down, make you sleepy, etc. It is hard to balance our different medical needs with the medicines we take. Sometimes a med may be good to help one symptom (e.g. anxiety) but then result in other bad symptoms (e.g. sleepiness). Perhaps ask yourself, which are the most important symptoms for you to deal with. If the sleepiness has assumed most importance for you now, maybe cut back on other meds and deal in different ways with more anxiety (or whatever the symptom is you are taking the sleepy drugs for).

I tend to get anemic and this makes me very tired. The best thing for me is to eat red meat semi-regularly. I really don't eat red meat that much, but my doc told me it would make me feel so much better, and she was right. I buy a large steak and cut it into strips and freeze them. Then I have one for breakfast a couple of times a week. Really helps. (I can't tolerate iron pills.) Anyway, don't rule out causes such as anemia, thyroid, etc., as suggested upthread.