Before the procedure, the Minor test is performed to precisely mark the areas of the skin affected with excessive sweat production. As part of the test, iodine solution is applied to the skin which is then dusted with potato starch (hence its common name – the starch-iodine test). After ten to twenty seconds the areas affected with highest sweat production become darker and are then marked accordingly to create a “map” for the physician performing the treatment. The botulinum toxin preparation is injected intradermally. The effect of the procedure in the form of reduced sweat production develops over several days.