Light stability of molsidomine in infusion fluids

The influence of artificial light, daylight or stimulated sunlight on the stability of molsidomine was investigated. In static experiments an 80 micrograms mL-1 solution of molsidomine in saline was stored in an unprotected infusion bag. During dynamic experiments the molsidomine solution (80 micrograms mL-1) was dropped at 12.5 mL h-1 from an unprotected infusion bag, from an infusion bag covered with aluminium-foil, or from an infusion bag protected with a UV-cover. Either unprotected infusion tubing or infusion tubing with a UV-filter were connected to the infusion bags. Static as well as dynamic experiments showed a half-life of about 20 min for the unprotected molsidomine solutions, when placed behind a window during a sunny day. Protection from light of the infusion bag but not of the infusion tubing had only a minor influence on the drug half-life. Protection of the infusion bag and the infusion tubing with a UV-filter increased the half-life to several days. These results confirm that both the infusion bag and the infusion tubing need adequate light protection during molsidomine administration.