Dacarbazine (
DTIC) is converted to the photo-degradation product
4-diazoimidazole-5-carboxamide (
Diazo-IC) by light.
Diazo-IC production is often responsible for the
pain reactions observed during peripheral
intravenous infusion of
DTIC in clinical settings. Although light shielding during infusion decreases the photo-degradation of
DTIC, its usefulness for the preparation of
DTIC has not yet been fully clarified. The aim of this study was to investigate the light conditions during the preparation of
DTIC solution in the compounding room from the viewpoint of the production amount of
Diazo-IC.
DTIC solution was prepared in the compounding room. Various light and temperature conditions and dissolving solutions during the preparation were investigated. The amounts of
DTIC and
Diazo-IC in solutions were determined using an HPLC coupled to UV detection. The photo-degradation of
DTIC was estimated by the amount of
Diazo-IC.
Diazo-IC production in the dissolving solutions increased in a time-dependent manner at 4 and 25°C under light shielding. Light exposure during the dissolving process did not affect the
DTIC and
Diazo-IC concentrations. Light shielding during dissolution did not alter the
Diazo-IC production until 4 h after dilution. In conclusion, short duration light exposure did not affect
Diazo-IC production. These findings suggest that light shielding is not needed in the preparation of
DTIC in the compounding room from the viewpoint of
Diazo-IC production.