Taking Old antibiotics ?

Okay my brother has a tooth infection and he needs antibiotics. I told him to call the dentist to make and appointment or to see if he has the ability to give him a prescription for some. He says hes gonna do it, but in the mean time he says he has these 2 year old antibiotics from 2006 that he is gonna take. I told him this is a bad idea. They are expired. What are the consequences of him taking these old pills?

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Answer:
Yes it's a bad idea. Specific antibiotics for specific conditions. In any case, you shouldn't have any leftover antibiotics, you're meant to finish the entire course, even if you get superior before they're completed.

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Answer:
It's a very bad idea. The medicine could have changed chemically in the intervening time and become harmful. It also could have weakened a lot and your brother would then be contributing to the problem of antibiotic resistant microbes. Just wait until you get to the physician and listen to her.

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Answer:
It can make the infection resistant to the antibiotic. They lose strength and their chemical compound changes.

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Answer:
The two peeps above stated it all.