Anyone know "why" meds have expiration dates.  Antibiotics, etc?  Was wondering if it was oxidation that made them lose effectiveness.  If so,  why not dump meds in a vacumn saver with a O2 absorber and then put them in storage??  

After the expiration date the potency starts to degrade and they won't be as effective.

Yes, but is that because of oxidation??  They are usually just in a prescription bottle.  I am guessing meds in blister packs last longer?  If so then meds stored in vacumn with a O2 absorber should last even longer...

Quoted: After the expiration date the potency starts to degrade and they won't be as effective.

One of our docs said that they should be OK for about a year and a half...

Now something like Amoxycillin(sp) goes bad pretty fast (liquid) if they even still
make it...

Some drugs turn toxic with age, or so I heard.

Quoted: Some drugs turn toxic with age, or so I heard.

I have zero medical training, so take this for what it's worth.

The only medication I've heard about "going toxic" is Tetracycline.  There are a bunch of Tetracycline derivatives that are chemically similar, so one might expect them to be subject to the same warning, but I've only heard it about Tetracycline.  For whatever that's worth.  Beyond that, no one has suggested that if the Tetracycline is a month or two past its expiration date it will be toxic.  I don't know how far beyond the expiration date this might become a problem, and I assume it would depend in part on the storage conditions.  In addition, my impression is that the newer studies indicate that modern Tetracycline does not really become toxic.  What's the truth?  I don't know.

Overall, I tend to believe that 98% of medications, over-the-counter and prescription, will lose potency over time but won't actually become harmful within a year or two of the expiration dates, and probably even longer in many cases.

Then again, I have zero medical training.

Tetracycline, if taken after the expiration can have serious, fatal side effects,...so yes there are downsides to taking old meds.  

but for those who feel like they need to stockpile meds, if the pills are expired, atleast look at the pills, if they are broken, crumbling, or a different color, dont take them, cause you wont know the dose, or exactly what you are taking.  

Yes, i have medical experience, im an EMT and a medical student ( so no i dont know everything)  and No this isnt medical advice.

For what its wroth, meds have expiration dates on em for a reason, so do what ya will