| Stress condition | Time | Assay of DRF (% w/w) | Mass balance (% w/w) | Remarks |
| Acid hydrolysis (0.5 N HCl) | 18 h | 85.3 | 99.8 | Two degradation products (A1 and A2) were observed |
| Base hydrolysis (1 N NaOH) | 24 h | 99.2 | 99.8 | No degradation was observed |
| Neutral hydrolysis (H2O) | 24 h | 99.7 | 99.7 | No degradation was observed |
| Oxidation (3% H2O2) | 10 days | 77.1 | 99.9 | Two degradation products (O1 and O2) were observed |
| Thermal (60˚C) | 10 days | 99.2 | 99.2 | No degradation was observed |
| Photo solid solution | 10 days | 99.7 99.5 | 99.7 99.5 | No degradation was observed |