Hello and welcome to healthcaremagic Telogen effluvium is the most likely reason for hair fall. Telogen is the resting phase of hair growth cycle. After any stressful event e.g drastic weight loss, medical illness like dengue, typhoid etc the hair gets shifted from the growth phase (anagen) to resting phase (telogen) which is manifested as increased shedding. Telogen usually begin 3 months after the stressful event and can last for 6 months following which the hair follicle re-enters the growing phase. I would suggest a healthy diet rich in nutrients and vitamins. A biotin supplement and an Iron supplement can be added to hasten the recovery from telogen. Since you have lost a good amount of weight. There out to be a some underlying reason for the weight loss. Thorough investigation is warranted along lines of lupus, malignancy, diabetes etc . I would suggest that you take an appointment with an internal medicine specialist and get thoroughly investigated. General symptoms like sun sensitivity, tiredness, fatigue, dizziness and inability to concentrate, drowsiness, low BP etc do warrant a consideration and investigation for Lupus besides malignancy, diabetes etc Since you have sun sensitivity, therefore you should use a broad spectrum sunscreen, throughout the day. regards