All perfect praise be to Allah, the Lord of the Worlds, and may His peace and blessings be upon our Prophet Mohammad and upon all his family and companions.
In the Noble Quran, Allah Himself has identified eight categories to whom Zakah is to be paid. He said {What means}, "Alms are for the poor and the needy, and those employed to administer the (funds); for those whose hearts have been (recently) reconciled (to Truth); for those in bondage and in debt; in the cause of God; and for the wayfarer: (thus is it) ordained by God, and God is full of knowledge and wisdom.Furthermore, Ziyad ibn al-Harith as-Suda'I narrated: "I came to the Messenger of Allah (PBUH) and swore allegiance to him, and after telling a long story he said: Then a man came to him and said: Give me some of the sadaqah (alms). The Messenger of Allah (PBUH) said: Allah is not pleased with a Prophet's or anyone else's decision about sadaqattill He has given a decision about them Himself. He has divided those entitled to them into eight categories, so if you come within those categories, I shall give you what you desire."{SunanAbiDawud 1630}.
The poor and the needy are amongst these categories. Therefore, it is permissible to give them Zakah under the condition that it is made into their possession, as indicated by the (لام) in the above verse. Al-Biqa`i said, "After mentioning the first four categories eligible to receive Zakah (the poor and the needy, and those employed to administer the (funds); for those whose hearts have been (recently) reconciled (to Truth), and that it should be made into their position, Allah, The Almighty, mentioned the other categories which are to be given Zakah to meet their particular needs: freeing a slave, settling a debt, fighting in the cause of Allah(Jihad) and for the wayfarer to reach his home, and this was indicated by in the same verse [Nadim Ad-Durar 505/8](في) .".
Moreover, Zakah is to be given to the poor once it is due on the giver and should be made into the former`s possession. An-Nawawi{May Allah have mercy on him} said, "Zakah is due immediately if possible: the giver has the money and there are eligible recipients."{Menhaj At-Talibeen, 72}.
In conclusion, it isn`t permissible to give the Zakah to the charitable organization to cover its various expenditures, such as salaries, rent and the like. Rather, it is permissible to give it to the poor patients who benefit from the services of the organization; provided thatthe Zakah is made into their possession. In addition, there is no harm in delegating the organization to receive the Zakah and divide it amongst them. And Allah knows best.