The Messenger of Allah ﷺ gave license to 'Abd al-Rahman b. 'Awf and al-Zubair b. al-'Awwam to wear silk shirts during a journey because of an itch which they had. (Using translation from Abū Dāʾūd 4056)
رَخَّصَ رَسُولُ اللهِ ﷺ لِلزُّبَيْرِ بْنِ الْعَوَّامِ وَلِعَبْدِ الرَّحْمَنِ بْنِ عَوْفٍ فِي لُبْسِ الْحَرِيرِ فِي السَّفَرِ مِنْ حِكَّةٍ كَانَتْ بِهِمَا