Opinions - Hydrocodone Syrup Shelf Life

[Kowawese]

SWIM was telling me about a bottle of Hydromet (Hydrocodone/Homatropine - no APAP) syrup they have which is almost 2 years old. SWIM's bottle of Hydromet is plastic and spent about 10 months boxed up in a non-climate controlled storage unit during which it was no doubt subjected to extremes in cold and hot found in SWIM's part of New York state. Otherwise it has been in a stable 72 degree environment.
SWIM was curious if this syrup is generally thought to still be safe to injest. SWIM said they have taken Hydromet many times in the past - in strict moderation - and enjoyed the effects. So they would rather not pour it down the drain. However, they are worried about things such as bacterial growth or toxins released from the plastic bottle.
Thank you for any ideas/information.