Having a health problem that is worsened by the use of water

Q: I have been afflicted with allergy lately, which caused me asthma. I have undergone several medical diagnoses by general practitioners and specialists, but I have not gotten better. This led me to travel to the city of Blida, located near Algiers to visit a medical specialist there. Through the medical examinations, it was found that I am afflicted with allergies. The physician treating me gave me some advice to avoid the allergy being aggravated. Among the guidelines offered by my physician is that I have to avoid using water in Janabah Ghusl (full ritual bath to cleanse of sexual discharge) after sexual intercourse. He advised me to resort to Tayammum (dry ablution with clean earth) instead of Ghusl. Thus, I would be grateful if you could tell me how to perform Tayammum after intercourse. May Allah guide you to what is good for you.

A: If, as you mentioned, using water for Ghusl after intercourse and other ritual impurities may harm your entire body, you should replace it with Tayammum with pure earth. If the use of water harms some parts of your body, you should wash the sound parts with water and perform Tayammum for the other parts of the body. As for the way you can perform Tayammum, you should make the intention to perform Tayammum, then mention the Name of Allah and strike pure earth with your hands to then rub your face with the inner surface of your fingers and the back of your hands with the inner surface of your hands. (Part No. 4; Page No. 171) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.