Allah has not sent down any disease except that He has also sent down the cure for it Sunan Ibn Majah 3437
Arabic hadith text
حَدَّثَنَا مُحَمَّدُ بْنُ الصَّبَّاحِ، أَنْبَأَنَا سُفْيَانُ بْنُ عُيَيْنَةَ، عَنِ الزُّهْرِيِّ، عَنِ ابْنِ أَبِي خِزَامَةَ، عَنْ أَبِي خِزَامَةَ، قَالَ سُئِلَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ أَرَأَيْتَ أَدْوِيَةً نَتَدَاوَى بِهَا وَرُقًى نَسْتَرْقِي بِهَا وَتُقًى نَتَّقِيهَا هَلْ تَرُدُّ مِنْ قَدَرِ اللَّهِ شَيْئًا قَالَ " هِيَ مِنْ قَدَرِ اللَّهِ "
Translation
It wasnarrated that Abu Khizamah said
“The Messenger of Allah (ﷺ)wasasked: ‘Do you think that the medicines with which we treatourselves, the Ruqyah by which we seek healing, and the means ofprotection that we seek, change the decree of Allah at all?’ Hesaid:‘They are part of the decree of Allah.’”