How to Take MiraLAX: Side Effects, Dosage
How to take MiraLAX for constipation: recommended dosage, timing, common side effects, and when to seek medical help.
Not medical advice. Speak with a healthcare professional before using any medication.
Reviewed by:
Updated Feb, 15
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Information sourced from FDA-approved prescribing information and peer-reviewed medical references.
How to Take MiraLAX
How to Take MiraLAX
Per OTC labeling, MiraLAX is taken by mixing the powder into a beverage. The following reflects standard label instructions.
- Per OTC labeling, adults and teens 17+: Use 1 heaping tablespoon (about 17 grams) of powder once daily.
- Per OTC labeling, children 6–16 years: Use 1–1.5 teaspoons (about 8.5 grams) once daily. Consult a clinician before use in this age group.
- Per OTC labeling, children under 6: Consult a clinician before use.
Per OTC labeling, mix the powder into 120–240 mL (4–8 oz) of liquid such as water, juice, or sports drink. Stir until fully dissolved.
- Per OTC labeling, take MiraLAX once a day, any time of day, with or without food.
- Maintain adequate fluid intake throughout the day.
- Per OTC labeling, if you miss a dose, take it the next day as scheduled — do not double up.
Warnings Before Taking MiraLAX
Per OTC labeling, do not use if you have symptoms of bowel obstruction such as severe abdominal pain, vomiting, or absence of bowel movements.
Per OTC labeling, consult your clinician if you have kidney problems or are on a low-sodium or fluid-restricted diet.
Per OTC labeling, ask your doctor first if you are pregnant, breastfeeding, or using other laxatives regularly.
MiraLAX Side Effects
Common
Mild
Bloating or Fullness
Per OTC labeling, mild bloating may occur as MiraLAX draws water into the colon.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
2–6 hours
Common
Mild
Gas
Per OTC labeling, some people may notice increased gas or mild cramping during use.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
2–6 hours
Common
Mild
Loose Stools
Per OTC labeling, MiraLAX can occasionally cause looser-than-usual stools. A dose adjustment, under clinician guidance, may be appropriate if this occurs.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
1–2 bowel movements (up to 24 hours)
Uncommon
Mild
Nausea
Per OTC labeling, a small number of people may experience mild nausea when using MiraLAX.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
30 minutes–2 hours
Common
Mild
Abdominal Cramping
Per OTC labeling, mild cramping may occur. If cramping is severe or persistent, discontinue use and consult a clinician.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
1–6 hours
Uncommon
Mild
Increased Thirst
Per OTC labeling, because MiraLAX draws water into the intestines, increased thirst may occur. Maintaining adequate hydration is recommended during use.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
1–3 hours
Contact Us for a Personalized Care Plan
Have questions about compounding? Contact Voshell's Pharmacy — we prepare patient-specific medications pursuant to valid prescriptions from your licensed prescriber.
What If You Forgot to Take MiraLAX
What If You Forgot to Take MiraLAX?
Per OTC labeling, if you miss a dose, take it when you remember as long as it is not close to the time for your next scheduled dose.
Per OTC labeling, skip the missed dose if you are near your next scheduled time.
Do not double up; taking extra doses is not recommended per product labeling.
Return to your normal schedule. Contact your clinician or pharmacist if you have questions about your dosing routine.
What If You Took Too Much MiraLAX
What If You Took Too Much MiraLAX?
Contact Poison Control at 1-800-222-1222 right away. For children or if an unusually large amount was ingested, seek urgent medical care immediately.
- Do not use additional doses until you have spoken with Poison Control or a clinician.
- If symptoms such as electrolyte imbalance signs (muscle weakness, irregular heartbeat) or severe diarrhea occur, seek emergency medical care.
- Keep this and all medications out of reach of children.
How Much Does MiraLAX Cost
MiraLAX Cost With Insurance
MiraLAX is an over-the-counter product. Coverage under insurance plans varies and depends on whether your plan includes OTC benefits.
Some plans with OTC benefits may provide partial or full reimbursement.
Without OTC benefits, retail pricing applies.
Store-brand products containing polyethylene glycol 3350 may be available at lower prices.
Contact your insurer to confirm whether OTC laxative coverage applies under your plan. Actual pricing varies by retailer and package size.
How Much Does MiraLAX Cost without Insurance
MiraLAX Cost Without Insurance
MiraLAX is an over-the-counter product available at most U.S. pharmacies and retailers. Prices vary by store, package size, and whether you choose the brand-name or a store-brand equivalent containing polyethylene glycol 3350.
Contact your local pharmacy or retailer for current pricing. Store-brand versions containing the same active ingredient may offer a lower-cost alternative.
Resources:
https://www.fda.gov/drugs/postmarket-drug-safety-information-patients-and-providers/miralax-patient-information
https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=17c0cd8b-e5ae-4d76-93a8-d4c2cb830b3e
https://medlineplus.gov/druginfo/meds/a602027.html
https://www.mayoclinic.org/drugs-supplements/polyethylene-glycol-3350-oral-route/description/drg-20515514
https://www.drugs.com/miralax.html
