4-Amino-N-(3,5-dimethyl-5-isoxazolyl)benzenesulfonamidecompound with 2,2 -iminobis[ethanol](1:1); 2,2 -iminodiethanol salt of N1-(3,4-dimethyl-5-isoxazolyl)sulfanilamide.This salt is prepared by adding enoughdiethanolamine to a solution of sulfisoxazole to bring thepH to about 7.5. It is used as a salt to make the drug moresoluble in the physiological pH range of 6.0 to 7.5 and isused in solution for systemic administration of the drug byslow intravenous, intramuscular, or subcutaneous injectionwhen high enough blood levels cannot be maintained byoral administration alone. It also is used for instillation ofdrops or ointment in the eye for the local treatment of susceptibleinfections.