I suffer from severe allergic rhinitis and have been using nose drops for the past six years to alleviate the severity of my condition. This becomes a problem in Ramadan because I know that nose drops are among the things which invalidate fasting.
However, the problem lies in that if I do not use it, I get severe colds and headaches. Last year while I was studying in a private university, I was forced to use nose drops. I tried to not let the drops reach my throat, but I could feel their taste. I would like to know the ruling of Islamic law on the above and on the status of my fast.