Yahya related to me from Malik from Abd al-Karim ibn Malik al- Jazari from Abd ar-Rahman ibn Abi Layla from Kab ibn Ujra that one time he was with the Messenger of Allah ﷺ in ihram, and he was suffering from lice on his head. The Messenger of Allah ﷺ told him to shave his head, saying, "Fast three days, or feed six poor people, two mudds for each person, or sacrifice a sheep. If you do any of those it will be enough for you."
أَنَّهُ كَانَ مَعَ رَسُولِ اللَّهِ ﷺ مُحْرِمًا فَآذَاهُ الْقَمْلُ فِي رَأْسِهِ فَأَمَرَهُ رَسُولُ اللَّهِ ﷺ أَنْ يَحْلِقَ رَأْسَهُ وَقَالَ صُمْ ثَلاَثَةَ أَيَّامٍ أَوْ أَطْعِمْ سِتَّةَ مَسَاكِينَ مُدَّيْنِ مُدَّيْنِ لِكُلِّ إِنْسَانٍ أَوِ انْسُكْ بِشَاةٍ أَىَّ ذَلِكَ فَعَلْتَ أَجْزَأَ عَنْكَ