Arabic text
عن سعد بن أبي وقاص رضي الله عنه قَال: عَادَنِي رسول الله صلى الله عليه وسلم فقال: «اللَّهُمَّ اشْفِ سَعْداً، اللَّهُمَّ اشْفِ سَعْداً، اللَّهُمَّ اشْفِ سَعْداً».
Translation
Sa‘d ibn Abi Waqqās (may Allah be pleased with him) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) visited me when I was ill and said: "O Allah, cure Sa‘d; O Allah, cure Sa‘d; O Allah, cure Sa‘d!"
Explanation
The Prophet (may Allah's peace and blessings be upon him) visited Sa‘d ibn Abi Waqqās, when he was sick and said three times: "O Allah, cure Sa‘d." This Hadīth indicates that it is from the Sunnah to visit a sick Muslim. It also indicates the Prophet's exemplary character, and his good manners with his companions, as he used to visit the sick and make supplication for them. This Hadīth serves as proof that it is desirable to make supplication saying: "O Allah, cure so and so," and one should name the person and repeat this supplication three times. This could be a reason for the person's recovery.
Source: HadeethEnc.com