Does penicillin stop working if you have too much of it over the years.

Yes, as with most medications you can build a resistence to it over time if you use it inproperly or are exposed to it frequently. This is especially true with antibiotics and pain medications, people are more likely to disregard the instructions for their effective use.

There's nothing better than penicillin if you can take it. In answer to your question I seriously believe anything is possible because even as a kid I was always able to take penicillin and good I could because I lived most of my life with ear infection. Several years ago in my 3o's I got phenomena and was given penicillin, it nearly killed me. I developed a reaction and was told I would never again be able to take it. So why??? I don't know.