Potency of expired hydrocodone syrup

[snarkymalarky]

SWIM recently stumbled across a fairly large bottle of hydrocodone syrup in his medicine cabinet from a surgery several years ago. It is generic, with 7.5 mg hydrocodone bitartrate and 500 mg acetaminophen per 15 ml in 9% alcohol. The label says to discard after February of 2003, 1 year after it was prescribed. What sort of loss of potency should SWIM expect? Is there anything else worth knowing about this stuff? (i.e. do any of those actives break down in something toxic?) FYIY, the syrup smells very "normal" (smells like medicine), and the liquid is clear, brownish yellow with no sort of sediment of any any kind. The bottle has been inside a dark cabinet at room temperature for the past 5 years. Thanks.