Thanks guys, just looked up some info on expiry dates:
Storage plays a big role in preserving the drug's potency. If your medicine is kept in your bathroom it will undergo changes due to the level of moisture deriving from the use of hot water in the shower or from the faucet. Direct sunlight and exposure to air such as in a not well closed bottle are other cases.
FDA conducted a study years ago requested by the military which proved that 90% of more than 100 drugs, were reported fine to use even 15 years after the expiration date!
Stuff I bought, boxed, sealed, hasnt moved from the store room in 8 years, no light or heat exposure, hopefully still some potency left.