Psyllium husk is a more traditional herbal medicine, psyllium husk is the dried and matured seeds of psyllium, a plant in the plantain family, usually obtained by harvesting the cob when the seeds are ripe in summer and fall, drying them in the sun, rubbing out the seeds, and removing impurities. It is a plant fiber that cannot be digested or absorbed, and because it is absorbent, it is used to treat both constipation and soft stools. Human use has the same effect.