Long-Term stability of irradiated solid-state pharmaceuticals

A set of four medications were exposed to mixed species beam simulated Galactic Cosmic Radiation (GCR) at the NASA Space Radiation Laboratory (NSRL) followed by a three-year storage period. The solid oral drug products (Acetaminophen [paracetamol] 500 mg tablets, Amoxicillin 500 mg capsules, Ibuprofen 400 mg tablets, and Promethazine 25 mg tablets) were selected based on operational relevance and previous testing experiments. Identical lots of each medication were assigned to four experimental groups: the non-irradiated Johnson Space Center control group, the non-irradiated traveling control group, the irradiation group I (GRSim, 0.5 Gy total dose), and the irradiation group II (GCRSim, 1.0 Gy total dose). Drug products were assessed for content of the active pharmaceutical ingredient (API) and the presence of degradation impurities. Dissolution testing was also performed to determine API release characteristics. Assessments were performed at 2, 18, and 34 months after irradiation.