How many pills of doxepin 25mg pills would it take before you overdose?

Depends. Doxepin is like Elavil (amitriptyline) and can interact with several other meds such that even a low dose can be toxic and some people don't metabolize well. You should discuss with your prescriber your concerns. Never take more than instructed. If thinking of a suicide plan, tell them as well. It's not a pleasant nor sure thing and other help is available if this isn't working.