Istinjaa with Zamzam water

Is it permissible to do Istinjaa’ (that is, to cleanse the private parts after urination or defecation with water) with Zamzam water?

There are authentic ahaadeeth that indicate that Zamzam water is noble and blessed. It is established in saheeh Muslim that the Prophet said regarding Zamzam water: "Verily, it is blessed; it is a food that satisfies one’s appetite.” In the version of Aboo Daawood with a strong chain of narrators, he added: ‘And a healing for sickness.”  This authentic hadeeth shows the merit of Zamzam water and that it is a food that satisfies one’s appetite, a healing for sickness and blessed. It is Sunnah to drink from it just as the Prophet (sallallaahu alayhi wa sallam) drank from it. It is permissible to perform ablution and Istinjaa’ with it. Similarly, it is permissible to do ghusl due to janaabah with it if there is need for such.

It is confirmed from the Prophet (sallallaahu alayhi wa sallam) that water gushed out from his fingers and people collected whatever they needed from this water in order to drink, perform ablution, wash their clothing and perform Istinjaa with it; each of these took place. If Zamzam water is not similar to the water that gushed out from the Prophet’s fingers, it is not superior to it; both of them are blessed water. So if it is permissible to perform ablution, ghusl, Istinjaa' and wash clothing with the water that gushed out from the Prophet’s fingers, it is also permissible with Zamzam water.

Nevertheless, Zamzam water is pure and palatable; it is recommended to drink from it and there is no harm in performing ablution with it or washing clothing with it or performing Istinjaa with it if there is need for that as preceded.

Source: Ahkaam al-Musaafir, pp. 12-13, by Shaykh Abdul-Azeez bin Baaz (may Allaah have mercy on him)