Osmotic laxatives exert a laxative effect by drawing water into the colon and retaining fluid in the bowel or by changing the pattern of water distribution in the feces. Unlike stimulant laxatives, they are safer and non-habit-forming. The most commonly used osmotic laxatives include magnesium hydroxide (“Milk of Magnesia”), magnesium citrate, magnesium sulfate (Epsom salts), sodium potassium tartrate, lactulose, glycerol and polyethylene glycol. Some are administered orally and others by enema.