How a sick person should pray if prevented from using water

This is a letter we received from the sender (N. A. H.) from the land of Banu al-Harith, the village of al-Shabashibah. She says: Your Eminence! Peace be upon you and Allah’s mercy and blessings. After that, I inform you that I have been afflicted with an illness and underwent a surgical operation in the hospital. Upon my discharge from the hospital, the specialist doctor informed me that I must not wash with water for a period of five months, including the blessed month of Ramadan. She says: I ask you to inform me whether I should remain as the doctor said for five months, or should I take a bath, pray, and fast in Ramadan?
Answer: The obligatory course is to follow the teachings in this matter; because an illness involving surgery and wounds may be affected by water. So, if the specialist doctor advises against using water, there is no harm; this is a dispensation for you. This is a dispensation to leave off water and use dry ablution, and this is sufficient. Dry ablution is sufficient. So, when the time for prayer comes, the person performs dry ablution and prays. You strike the earth with your hands and wipe your face and palms for prayer, and this is sufficient. Do not take a bath with water until the period determined by the doctor has passed.
As for fasting, if he forbade you from fasting and said that it would harm you, then do not fast, and make it up afterwards. And if he did not say anything to you about fasting, then you fast. You fast in Ramadan with the people.
So, the result is that the doctor is relied upon in these matters, if the doctor is trustworthy and is a specialist in the field and is known, then his word is acted upon in this matter regarding leaving off water and leaving off fasting; because fasting may harm the sick person, and water may harm him. The specialist doctor is the one who knows these things. So, if he determines for the sick person that he should not use water or should not fast, there is no barrier to acting accordingly. One acts accordingly to preserve his health. And our Lord, Mighty and Majestic, is the Most Merciful of the merciful, Glorified and Exalted is He. He has shown mercy to His servants and permitted them what benefits them and left off what harms them. So, He made the sick person and the traveler break their fast. It is prescribed for the sick person and the traveler to break their fast to preserve the health of the sick person and to ease things for the traveler, for he may be afflicted with hardship. So, Allah, Glorified and Exalted is He, is the Most Merciful of the merciful. So, the One who granted the sick person a dispensation to break his fast so that fasting would not harm him, likewise, his leaving off water so that water would not harm him. The ruling is one. And likewise, if fasting harms him, by the text of the Qur'an. Yes.