u/Electrical-Hurry-643

I have a quick question, i reconstituted my tirz on 4/20. It was a 30ml bottle and I am only taking 2.5 right now weekly. It’s coming up on a month that I have had it in the refrigerator. Initially I assumed wow this will last me awhile bc I am only using so little, but then I read that it is only good for 28 days. Is that true? I have to just trash almost an entire bottle? I am new to peptides so I’m curious what everyone does bc I know a lot of people are on lower doses for a bit so are we just trashing it and replacing it every month? Thanks in advance for any information.