fā​fēng

go crazy

发疯 (發瘋) fā​fēng
go crazy verb
to act in an irrational, wild, or extreme manner

You bought something so expensive; have you gone mad?

go mad verb
to lose one's sanity or suffer from a mental illness

He went mad because of the severe shock.

Frequency

Movie subtitles
23.7 per million appears in 10% of films
Written text
4.14 per million

Sources

Definitions
CC-CEDICT