be off your head idiom mainly UK informal
发疯，精神错乱
to be crazy
You must be off your head going out in this weather! 这种天气出去你真是发疯了！
UK喝醉了;毒瘾发作
to not be in control of your behaviour because you have drunk too much alcohol or taken drugs
Hannah was off her head as usual. 汉娜又喝醉了。