Hi @paulita teriparatide (generic for brand Forteo) is known to cause fatigue or tiredness, mostly because it reduces blood pressure. Many members on this forum had this effect when staring Forteo. Personally I experienced it during first one and a half months of Forteo treatment. As many had described, drink enough water (10 cups or 2400cc water daily) can help. If blood pressure is still on the low end, adding some salt to water or eating some salty snacks will help further. The discussions were scattered in different threads, if you search Forteo, they might lead you to some of the discussions. Hope you feel better soon.