what is the dose for Miralax
The usual dose is 17 grams (about 1 heaping tablespoon) of powder per day (or as directed by physician) in 4 to 8 ounces of water. Each bottle of MiraLax (polyethylene glycol 3350 - otc) is supplied with a measuring cap marked to contain 17 grams of laxative powder when filled to the indicated line.One to 3 days (24 to 72 hours) may be required to produce a bowel movement.Directions. 1  Do not take more than directed, unless advised by your doctor.n powdered form, for oral administration after dissolution in water. MiraLax (polyethylene glycol 3350 - otc) is available in two sizes; a 8.3 oz. container and a 4.1 oz. container of laxative powder.