Hello I have gone through your question and understand your concerns. Easy fatigue and generalized weakness can be caused by deficiency of various essential nutrients in the body. Becadexamin taken once daily, after breakfast can be beneficial to health and improve the symptoms of fatigue. It can be taken as long as you feel the need or continued to improve overall health and well being. It can also be low levels of vitamin D and iron, better get a blood test done for vitamin D levels along with complete blood picture. Vegetarians are prone to suffer with deficiency of vitamin D more often, consider sun exposure at mornings for at least 10 minutes daily along with regular moderate physical activity. Get eye examination done by the optometrist and avoid reading in poorly lit area. Hope your concern is answered. Thank you.