have a toothache 和have toothache 都对吗?

问题描述:

have a toothache 和have toothache 都对吗?
小学生快乐英语课本中讲到的知识点 have a toothache,
但是在课文阅读中有一处这样说的:I often have toothache.
也可以用 have toothache 吗 ,固定搭配不是have a toothache?
望通的高手指教,谢谢

have a+形容词+toothache
固定have toothache ,印象中是这样