May 30, 2016


(polyethylene glycol 3350) - OTC


A white powder for reconstitution. MiraLax (polyethylene glycol 3350, NF) is a synthetic polyglycol having an average molecular weight of 3350. The actual molecular weight is not less than 90.0 percent and not greater than 110.0 percent of the nominal value. The chemical formula is HO(C2H4O)n H in which n represents the average number of oxyethylene groups. Below 55° C it is a free flowing white powder freely soluble in water.

MiraLax (polyethylene glycol 3350 - otc) is an osmotic agent for the treatment of constipation.

What are the possible side effects of polyethylene glycol 3350 (GlycoLax, MiraLax)?

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop taking polyethylene glycol 3350 and call your doctor at once if you have any of these serious side effects:

  • severe or bloody diarrhea;
  • bleeding from your rectum;
  • blood in your stools; or
  • severe and worsening stomach pain, cramping, or bloating.

Less serious side effects may include:

  • bloating, gas, upset stomach;
  • dizziness;...

Read All Potential Side Effects and See Pictures of MiraLAX »

What are the precautions when taking polyethylene glycol 3350 - otc (MiraLAX)?

Before taking this medication, tell your doctor or pharmacist if you are allergic to polyethylene glycol; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: certain stomach/intestinal problems (bowel obstruction).

Before using this medication, tell your doctor or pharmacist your medical history, especially of: persistent nausea/vomiting/abdominal pain, other stomach/intestinal problems (irritable bowel syndrome), kidney disease.

Caution is advised when using this drug in the elderly because...

Read All Potential Precautions of MiraLAX »

Last reviewed on RxList: 7/25/2007
This monograph has been modified to include the generic and brand name in many instances.

MiraLAX - User Reviews

MiraLAX User Reviews

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