I am not sure what is causing my eyebrows falling out but itâs like the ends of them as the outer third part seems to be gone completely. Itâs really hard for me to find out that what exactly is causing it because of number of things that has started two years ago. I went on birth control pills, then my asthmas and taking allergy shots. Or may be itâs because of lack of protein as I donât eat meat and my thyroid was low. I asked my gynecologist but she said that she donât think so that it is because of birth control pills. Anyone can tell me what the reason is? It really sucks not having that much eyebrows.