"If you say that once more I'll scream my head off!"

At the very least, she'd be trying to scream her head off.

A person shut in down here could scream her head off, and no one outside would hear.

If she couldn't reason with him, she'd scream her head off.

The engine was still screaming its head off so he stopped it.

It was hard not to join the private in screaming his head off.

Had he realized that she was about to scream her head off?

But no, his medical monitor would have been screaming its head off if anything like that had happened.

She could probably scream her head off, and no one would come.

By the third day, she was screaming her head off.