MiraLAX (polyethylene glycol 3350) is an over-the-counter drug that’s taken to treat constipation. The drug comes as a powder that you usually take once per day.
MiraLAX is used in people ages 17 years and older to treat constipation. The drug helps to produce a bowel movement in 1 to 3 days.
The active ingredient in MiraLAX is polyethylene glycol 3350. MiraLAX belongs to a group of drugs called osmotic laxatives. These drugs work to soften stools and increase bowel movement frequency by drawing water into the bowel.
This article describes the dosage of MiraLAX, as well as its strength and how to take it. To learn more about MiraLAX, see this in-depth article.
The dosage chart below highlights the basics of MiraLAX’s dosage.
| Age range | Recommended dosage |
|---|---|
| younger than 17 years old | Talk with your doctor. |
| 17 years and older | 17 grams (g) once per day |
Keep reading for more details about MiraLAX’s dosage.
What’s MiraLAX’s form?
MiraLAX is available as a powder. You mix the powder with liquid to make an oral solution.
What strength does MiraLAX come in?
MiraLAX comes in one strength of 17 g.
What’s the usual dosage of MiraLAX in adults?
The information below describes dosages that are commonly taken or recommended. But be sure to take the dosage your doctor recommends for you. They’ll determine the best dosage to fit your needs and usually the smallest dosage that provides the desired effect.
Dosage for constipation in adults
The typical MiraLAX powder dosage for adults with constipation is 17 g once per day. Do not take MiraLAX for more than 7 days unless your doctor recommends it.
What’s the dosage of MiraLAX for children?
MiraLAX is taken to help treat constipation in children ages 17 years and older. For children under 17 years old, talk with your child’s doctor before they take MiraLAX.
The dosage for kids ages 17 years and older is the same as the dosage for adults. To learn more, see the “What’s the usual dosage of MiraLAX in adults?” section.
For more information about MiraLAX’s dosage for children, talk with your child’s doctor or a pharmacist.
How to take MiraLAX
MiraLAX comes as a powder that you mix with liquid to make a solution that you drink. You can measure the dose using the bottle cap. Fill the bottle cap with the powder to the top of the white section, which is equal to 17 g. Or use a single-serve packet of MiraLAX, which is also equal to 17 g.
Mix the powder with 4 to 8 ounces of liquid. The liquid can be hot, cold, or room temperature. Stir the liquid mixture. Be sure the powder is fully dissolved and the liquid has no clumps. Then, drink the full mixture.
Is MiraLAX taken long term?
No, you usually take MiraLAX as a short-term treatment for constipation. Talk with your doctor if you have constipation that lasts longer than 7 days. Your doctor can help you decide the best treatment for your constipation.
Do not take more MiraLAX than your doctor recommends, as this can lead to harmful effects.
What to do in case you take too much MiraLAX
Call your doctor right away if you think you’ve taken too much MiraLAX. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.
Below are answers to some commonly asked questions about MiraLAX’s dosage.
How much MiraLAX can I take for severe constipation?
The recommended dosage for constipation is 17 g once per day. The drugmaker’s label provides only this dosage. Also, it has no recommendations for taking MiraLAX multiple times per day.
Do not take more MiraLAX than your doctor recommends.
If your constipation lasts longer than 7 days or isn’t improving, talk with your doctor. They can help you decide the best treatment for your constipation.
What’s the MiraLAX dosage for adults in tablespoons or teaspoons?
MiraLAX dosage isn’t measured in tablespoons or teaspoons per the drugmaker’s label. You measure MiraLAX’s dosage using the bottle cap. With this method, you fill the cap with powder to top of the white section. This is equal to 17 g.
If using the single-serve packets, one single-serve packet equals 17 g.
Talk with your doctor or pharmacist if you have additional questions on how to measure MiraLAX.
What time of day should you take MiraLAX?
You can take MiraLAX at any time of the day. The manufacturer’s label doesn’t have recommendations regarding the best time to take MiraLAX. But you might consider taking MiraLAX in the morning. This may help you avoid having to wake in the night for a bowel movement.
Talk with your doctor or pharmacist if you have additional questions about when to take MiraLAX.
Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.
