Answered by Shaykh Faraz Rabbani
There is only a very small portion of my face (about the size of a coin) that I can’t wash because of a medical reason. Shall I perform tayammum in full? Or shall I just perform wudu and rub dry hands (with earth) on that part that I can’t wash?
Walaikum assalam wa rahmatullah,
I pray that this finds you well, and in the best of health and spirits. May Allah grant you all good and success in this life and the next.
In such a case, if you can wipe the area instead of washing, without harship, then do so. If you can’t, then you can skip even wiping it, and your wudu will be valid, and no tayammum is required. [ Shurunbulali, Maraqi al-Falah ]
And Allah alone gives success. Faraz Rabbani