Answered by Shaykh Faraz Rabbani
What is the famous dhikr against depression?

Walaikum assalam wa rahmatullah,
There are many. In general, the remembrance of Allah drowns sorrows: when the light of the Infinite shines on our hearts, the shadows of finite concerns scatter.
Allah Most High said,
“Verily in the remembrance of Allah do hearts find rest.” [Qur’an, 13.28]
One dhikr that the scholars have found to be particularly effective is the famous Salat al-Tibbiyya. [attached]
See answer(s) below.
Wassalam,
Faraz Rabbani