اللَّهُمَّ رَبَّ النَّاسِ، أَذْهِبِ الْبَأْسَ، اشْفِ أَنْتَ الشَّافِي، لَا شِفَاءَ إِلَّا شِفَاؤُكَ، شِفَاءً لَا يُغَادِرُ سَقَمًا
Purpose Ask Allah, the Lord of mankind, for cure.
When to Use Read this when visiting or praying for someone who is ill.
Source Sahih al-Bukhari and Sahih Muslim

Transliteration

Allahumma rabban-nas, adh-hibil-ba`s, ishfi antash-shafi, la shifa`a illa shifa`uk, shifa`an la yughadiru saqama.

Meaning

O Allah, Lord of mankind, remove the harm and heal, for You are the Healer. There is no healing except Your healing, a healing that leaves no illness.