Nitrofurantoin - I took medicine without knowing the expired date?

I took 3 yrs old expired nitrofurantoin 100mg. I began to itch all over & once I stopped, itching did too!

A bit late in responding... But, it should not hurt you. It is likely expired based on the date that you received it. Most pharmaceuticals have a 2 year expiry date. They do retain some potency after the expiration date. Usually about 6 to 12 months depending upon the drug...

Hello. If the pills were stored carefully, no high heat and no cold temperatures it may still be. But if not, throw it.

But the real question is why do you have left overs and why are you medicating yourself without a urine test? Burning, itching and even blood may not be a urine infection. It could also be an STD. Please get tested properly so you can actually be treated for the right disease.