Your dr or pharmascist don't know squat about expiration dates unless
they're paying far more attention than the average bear. It was recently
revealed that expiration dates are based on protecting the pharmaceutical
companies, not on medical issues, because of hoops the FDA requires to
establish longer dates. It's easy to prove a med lasts one year (three
centuries for Metamucil, I think), so they slap a safe, sure, short date on
it so the lawyers and the FDA can't hang 'em out to dry later. In fact,
MANY, probably most, meds are just fine for at least twice the advertised
time. But when you call the drs or pharmacies you get the party line.

I.P.

Neither your doctor or pharmacist will give you a precise answer here as
they simply don't know. Expiration dates are set by the manufacturer.
They have no incentive to set dates beyond the time necessary to move
the product through the supply chain and into the hands of the patient.

I wouldn't recommend that you increase your dose unless you're not
getting the result you need, and certainly not unless you've conferred
with your doctor.

Many tablets have an extended shelf life if they're stored at controlled
room temperature, and not exposed to excess light or moisture. Under
optimal storage conditions a five year shelf life isn't unusual (for
tablets).

Most pharmaceutical manufacturers will assign expiration dates well
within the proven stability limits, to account for variations in
shipping and storage conditions.

Check with your doctor, he will probably let you go a year beyond the
printed date, if you've stored the pills properly (and guess what - the
bathroom cabinet isn't the best place when you consider the moisture
generated in by the shower).