Du'a when drinking Zamzam water

اللَّهُمَّ إِنِّي أَسْأَلُكَ عِلْمًا نَافِعًا، وَرِزْقًا وَاسِعًا، وَشِفَاءً مِنْ كُلِّ دَاءٍ

Allahumma inni as'aluka 'ilman nafi'an, wa rizqan wasi'an, wa shifa'an min kulli da'

O Allah, I ask You for beneficial knowledge, abundant provision, and a cure from every disease.

Reported from Ibn ʿAbbās (may Allah be pleased with him) when drinking Zamzam, in Sunan al-Dāraquṭnī 2738 and al-Mustadrak of al-Ḥākim; not a narration from the Prophet (peace be upon him).