Authentic
Sunan Abu Dawud 3887
The Messenger of Allah (ﷺ) entered when I was with Hafsah, and he said to me: Why do you not teach this one the invocation for skin eruptions as you taught her writing?
أَلاَ تُعَلِّمِينَ هَذِهِ رُقْيَةَ النَّمْلَةِ كَمَا عَلَّمْتِيهَا الْكِتَابَةَ "