It wasnarrated from Anas bin Malik that the Messenger of Allah (ﷺ)granted a concession to Zubair bin 'Awwam and 'Abdur-Rahman bin'Auf,allowing them to wear silk shirts, because of a rash theyweresuffering from. (DE)
English reference (DE): Vol. 4, Book 32, Hadith 3592 (DE)
Arabic reference (DE): Book 32, Hadith 3723 (DE)