Mishkat al-Masabih 4569
Abu Huraira told that when some of the companions of God's messenger remarked to him that truffles are the smallpox of the earth he replied:
“Truffles are a kind of manna, and their juice is a remedy for the evil eye. The 'ajwa dates come from paradise, and they are a remedy for poison.” 
Abu Huraira said that he took three, five, or seven truffles, pressed them, put their juice in a bottle and applied it as an eye-lotion to a slavegirl of his who was blear-eyed, and she recovered. 

Tirmidhi transmitted it, saying this is a hasan tradition.
وَعَن أبي هريرةَ إِنَّ نَاسًا مِنْ أَصْحَابِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالُوا لرسولِ الله: الْكَمْأَةُ جُدَرِيُّ الْأَرْضِ؟ فَقَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «الْكَمْأَةُ مِنَ الْمَنِّ وَمَاؤُهَا شِفَاءٌ لِلْعَيْنِ وَالْعَجْوَةُ مِنَ الْجَنَّةِ وَهِيَ شِفَاءٌ مِنَ السُّمِّ» . قَالَ أَبُو هُرَيْرَةَ: فَأَخَذْتُ ثَلَاثَةَ أَكْمُؤٍ أَوْ خَمْسًا أَوْ سَبْعًا فَعَصَرْتُهُنَّ وَجَعَلْتُ مَاءَهُنَّ فِي قَارُورَةٍ وَكَحَّلْتُ بِهِ جَارِيَةً لِي عَمْشَاءَ فَبَرَأَتْ. رَوَاهُ التِّرْمِذِيُّ وَقَالَ: هَذَا حَدِيثٌ حسن