Griseofulvin was recrystallized from organic solutions using a liquid antisolvent crystallization technique. Griseofulvin was dissolved in organic solvents and the solutions were mixed with an aqueous antisolvent leading to a particle precipitation. Process variables such as temperature, concentration of solution, and solution injection rate were manipulated during the crystallization experiments. In particular, an ultrasonic wave was applied to the mixture of the solution and antisolvent in order to investigate the effect of ultrasound on the properties of the precipitated crystals. The intensity of the ultrasonic waves, the sonication time and the moment when the ultrasonic waves were applied were all regulated during the crystallization experiments. The size of the crystalline particles decreased when the concentrations of griseofulvin in the organic solutions increased. Smaller particles were produced when the griseofulvin solution was rapidly injected into the antisolvent. A higher heat of fusion for the crystalline particles was observed when the crystals were precipitated at lower temperatures. A significant reduction in particle size was achieved as the intensity of the ultrasonic waves and the duration of sonication increased during the crystallization experiments. (C) 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.