To be more specific I have the Omnitrope® (Somatropin [rDNA origin] Injection) 10 mg/1.5 mL cartridges, and the cartridges have not been exposed to sunlight, but have been laying around my room since May 2014. The expiration date is still good!
Should I still use my Omnitrope if it has not been refrigerated for a few weeks?