Using Medication When Unable to Endure Pain

The Messenger of Allah (s):
تَجَنَّبِ الدَّوَاءَ مَا احْتَمَلَ بَدَنُكَ الدَّاءَ فَإِذَا لَمْ یَحْتَمِلِ الدَّاءَ فَالدَّوَاء؛
“Avoid medication as long as your body can tolerate the pain, but when it cannot, then use medication.”
Makarem Al-Akhlaq: 362