Lobenzarit disodium (LBD) salt is a drug used in the treatment of rheumatoid arthritis diseases. The objective of this work is to propose and validate a method for selecting the best wetting agent allowing to obtain spherical agglomerates during crystallization. This method is based on the so-called Washburn's test (capillary rise of liquids in a granular medium). Crystallization tests carried out at different conditions showed that the best results were obtained in the presence of n-hexane that was effectively found to be a better wetting liquid of the lobenzarit crystals than the other solvents.