We used to do ruqyah (healing) in the time of jahiliyyah. We asked, O Messenger of Allah, what do you say about it? He said: Let me know your ruqyah (healing) and said: There is no harm in the ruqyah which does not contain any shirk.  

كُنَّا نَرْقِي فِي الْجَاهِلِيَّةِ فَقُلْنَا يَا رَسُولَ اللَّهِ كَيْفَ تَرَى فِي ذَلِكَ فَقَالَ اعْرِضُوا عَلَىَّ رُقَاكُمْ لاَ بَأْسَ بِالرُّقَى مَا لَمْ يَكُنْ فِيهِ شِرْكٌ  

In the pre-Islamic period we used to apply spells and we asked: Messenger of Allah ! how do you look upon it ? He replied : Submit your spells to me. There is no harm in spells so long as they involve no polytheism. (Using translation from Abū Dāʾūd 3886)   

كُنَّا نَرْقِي فِي الْجَاهِلِيَّةِ فَقُلْنَا يَا رَسُولَ اللَّهِ مَا تَقُولُ فِي ذَلِكَ؟ قَالَ «اعْرِضُوا عَلَيَّ رُقَاكُمْ وَلَا بَأْسَ بِالرُّقَى مَا لَمْ يَكُنْ شِرْكًا»