I know this will sound vague - but it really depends on the health of each person and on the type of parasite being removed. Drinkng at least 2 quarts of water per day will help with the quick removal of toxins.
Some folks do break out, but it usually only lasts for a few days or so - HUMAWORM contains burdock which is the greatest skin purifier in the herbal kingdom. It will help keep break outs to a minimum.