You should not use MiraLAX if you have a bowel obstruction or intestinal blockage. If you have any of these conditions, you could have dangerous or life-threatening side effects from MiraLAX.
People with eating disorders (such as anorexia or bulimia) should not use MiraLAX without the advice of a doctor.
Before taking MiraLAX, tell your doctor if you are allergic to any drugs, or if you have ulcerative colitis, irritable bowel syndrome, kidney disease, nausea or vomiting with severe stomach pain, or if you have had a sudden change in bowel habits that has lasted 2 weeks or longer.
MiraLAX should produce a bowel movement within 1 to 3 days of using the medication. Polyethylene glycol 3350 normally causes loose or even watery stools.
Do not use MiraLAX more than once per day. Call your doctor if you are still constipated or irregular after using this medication for 7 days in a row.
Before taking this medicine
You should not use MiraLAX if you are allergic to polyethylene glycol, or if you have a bowel obstruction or intestinal blockage. If you have any of these conditions, you could have dangerous or life-threatening side effects from polyethylene glycol 3350.
People with eating disorders (such as anorexia or bulimia) should not use this medication without the advice of a doctor.
To make sure this medicine is safe for you, tell your doctor if you have:
nausea, vomiting, or severe stomach pain;
ulcerative colitis;
irritable bowel syndrome;
kidney disease; or
if you have had a sudden change in bowel habits that has lasted 2 weeks or longer.
FDA pregnancy category C. It is not known whether MiraLAX will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.
It is not known whether polyethylene glycol 3350 passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.
 MiraLAX pregnancy and breastfeeding warnings (more detail)
How should I take MiraLAX?
Use MiraLAX exactly as directed on the label, or as it has been prescribed by your doctor. Do not use this medicine in larger or smaller amounts or for longer than recommended.
To use MiraLAX powder, measure your dose with the medicine cap on the bottle. This cap should contain dose marks on the inside of it. Pour the powder into 4 to 8 ounces of a cold or hot beverage such as water, juice, soda, coffee, or tea. Stir this mixture and drink it right away. Do not save for later use.
MiraLAX should produce a bowel movement within 1 to 3 days of using the medication. Polyethylene glycol 3350 normally causes loose or even watery stools.
Do not use MiraLAX more than once per day. Call your doctor if you are still constipated or irregular after using this medication for 7 days in a row.
Store at room temperature away from moisture and heat.
