Dua while drinking zam zam
The Lord of Madinah the comfort of our hearts and minds, the holy Prophet sallallaahu alaihi wasallam saying is that: “The purpose of drinking zam zam is achieved.” (Sunan Ibn Maajah, Volume 3, Page 490, hadith: 3062).
Dua
اَللّٰھُمَّ اِنِّیْ اَسْءَلُکَ عِلْمًا نَّافِعًا وَّرِزْقًا وَّاسِعًا وَّشِفَآءً مِّنْ کُلِّ دَآءٍط
“Oh Allah, I implore from you the beneficial knowledge, abundance of provision and good health from every disease.”
Question :  Zam zam too should be taken in with three gulps?
Answer : Yes. It is the ruling for everything.
It has been narrated in a hadith:
فَاشْرَبُوْہ، مَصًّا وَلَا تَشْرَبُوْہ، عَبًّا فَاِنّ الْعَبَّ یُوْرِثُ الْکِبَادُ
Sip while drinking, avoiding large gulps because it causes disease to the liver.(Al-Jaame’ Al-Sagheer, hadith :710, volume 1, page 49) (Malfuzaat Aala Hadrat, page: 434)