Error when terminal opens; no available formular

When I open my terminal I see the following message

Last login: Thu Dec 18 22:00:53 on ttys000
Error: No available formula for php5

I have tried to run brew doctor but the error remains. I am using homebrew dd7511b3

If I run brew remove php5, I get

Error: No such keg: /usr/local/Cellar/php5

How can I resolve this issue?