How Long Does It Take For Miralax To Work?

Constipation is a troublesome health issue that puts a person in serious discomfort and uneasiness.

Symptoms of severe constipation, such as cramping and abdominal pain, bloating, gas, and trouble with bowel movements are quite unbearable for the sufferer.

Miralax® and Metamucil® are some of the best OTC medications to treat constipation; regular colon cleansing also aids in weight loss.

A first-time user of Miralax will be eager to know, “how long does it take to work?” The patient has a sense of urgency to get relief, so he looks forward to getting a fast result with it.

Miralax usually takes 1 to 3 days to produce a bowel movement. People with severe bowel or digestive issues may take longer to see results.

Certainly, Miralax is useful but its effectiveness and speed depend on several factors. In the rest of this article, you’ll read all the important facts that every user of this supplement should be aware of.

Uses and Benefits of Miralax

Miralax is an osmotic laxative used to remedy occasional constipation.

It softens the stool by retaining a considerably large amount of water in the stomach.

It is an osmotic-type ecoprotec that promotes smooth and frequent bowel movements.

Miralax comes as a powder only. It’s an over-the-counter medication that can be procured without a doctor’s prescription.

Many people use it as a do-it-yourself medication for dealing with bloating, constipation, and stomach cramps.

Miralax can be used for bowel evacuation before colonoscopy in addition to relieving occasional constipation. It is also used as a colon cleanse supplement.

It was in 1999 Braintree Laboratories first introduced Miralax as a prescription medicine for irregular and difficult bowel movements in adults.

Having found polyethylene glycol 3350 was safe and effective for use, in 2006 Food and Drug Administration (FDA) granted permission to sell Miralax as an over-the-counter (OTC) medication for occasional constipation.

Since then, Miralax is the most popular anti-constipation medication used by thousands of people all over the world.  Polyethylene glycol 3350 is sold under several brand names. The “3350” qualifier refers to the molecular weight of this particular variant of PEG.

How Long Does Miralax Take to Start Working?

Patients using this laxative for the first time are eager to know how fast Miralax works.

It usually produces bowel movements in 1 to 3 days of use.

Most people get the desired result from Miralax after 12 hours of taking the first dose itself.

The speed at which Miralax works depends on the lifestyle and diet habits of the individual. This laxative begins to take its effect in the intestine within a few hours after consuming the first dose.

Drinking enough water, having a more fiber-rich diet, and doing physical exercises can give a faster result from Miralax.

Frequently Asked Questions – FAQs 

How does Miralax work?

Polyethylene glycol is an osmotic laxative that causes a bulking effect in the colon by retaining water in the stomach. It binds water to the stool which results in the loosening of the stool. It also helps to increase the weight of the stool which forces a fecal evacuation.

Stimulant lenitive causes muscle contractions in the intestines forcing the evacuation of wastes from the bowel. Unlike other stimulants, Miralax does not quicken the transit time in the gastrointestinal tract.

It does not cause a sudden urge to rush to the lavatory so you can take it without the fear that it might interrupt your day.

Store it at room temperature away from moisture and heat.

How to use Miralax?

It is easy and comfortable to use MiraLax which comes in powder form with no taste and odor.

Take the recommended measure of this laxative in powder form using the cap of the bottle. Inside of the cap has lines indicating the amount of powder to be used per 1 dose.

Mix the powder into 4 to 8 ounces of hot or cold beverages like juice, coffee, tea, water, soda, or smoothies. Stir the mixture well and drink it right away.

Miralax Results

What is the dosage of Miralax powder per day?

The recommended dose of Miralax per day is 17 grams (one capful) in 8 ounces of liquid. Doctors and manufacturers recommend only one dose of this stool softener per day. Consume one dose per day to achieve the desired result.

When it is used for colonoscopy prep, you can use a higher dosage in conjunction with large volumes of water.

What is the dose of Miralax for children?

There have been a lot of discussions on administering Miralax to children. Most physicians recommend Miralax for kids older than 6 months old.

Miralax doses for kids vary according to body weight, and purpose of use.

Occasional constipation:

  • Children greater than 6 months of age: 0.5 to 1.5 g/kg daily (initial dose 0.5 g/kg; titrate to the effect)
  • Maximum dose: 17 g/day

Fecal impaction:

  • Children greater than 3 years of age: 1 to 1.5 g/kg daily for 3 days
  • Maximum dose: 100 g daily

Bowel preparation:

  • Children greater than 2 years of age: 1.5 g/kg/day
  • Maximum dose: 100 g daily

What are the possible side effects of Miralax?

The risks of side effects are minimal. Most people who use this stool loosener improve bowel movement without harsh side effects.

However, Miralax overdose or regular use of it for a long period may report side effects.

Some of the common side effects of Miralax are:

  • nausea,
  • abdominal cramping,
  • severe diarrhea,
  • gas formation,
  • heartburn,
  • dizziness,
  • stomach pain,
  • persistent diarrhea,
  • an excess number of bowel movements
  • bloody stools,
  • rectal bleeding.

If you experience any physical discomforts after using Miralax, stop taking it, and you should promptly consult your doctor.

In a few rare cases, Miralax can cause allergic reactions such as:

  • itching,
  • rashes,
  • swelling of rashes affected area,
  • severe dizziness,
  • breathing difficulties.

Generally, Miralax doesn’t produce any serious side effects. The ingredients in it are not absorbed by the body and do not cause tachyphylaxis (i.e., diminishing effects with overuse) as many stimulant bowel cleansers do.

Does Miralax cause drug interaction?

Some of the medications may interact with Miralax, for it contains polyethylene glycol 3350.

When your doctor recommends it, you should inform the doctor of other prescription medicines that you are using.

Follow the instructions of your doctor or pharmacist for taking other medications along with it.

Always keep a list of all your medications with you, and show the list to your pharmacist or doctor.

How Long Does Miralax Take To Work

What are the diet modifications required for fast results?

Patients suffering from constipation need to eat a minimum of 25 grams of soluble fiber per day. Some of the fiber-rich foods are cereals, fruits, and leafy vegetables.

Children suffering from constipation must be encouraged to drink about 35 to 55 ounces of water per day. Adults should drink about 60 to 70 ounces of water per day to ward off constipation.

Avoid having certain foods that have a reputation for being “binding” or constipating foods. Some of the common foods bad for constipation are dairy products, red meat, frozen foods, cookies, bananas, and fried foods.

Engaging in active physical exercises daily for 30 minutes to 1 hour is necessary for getting fast relief from constipation.

Can anyone use Miralax?

If you are allergic to polyethylene glycol, this anti-constipation medication is not your cup of tea.

Some of the inactive ingredients in the product may cause allergic reactions or other health issues depending on your health conditions.

Patients who suffer from certain intestinal or stomach problems like bowel obstruction or others don’t take Miralax.

Do not use this medication if you have health issues such as persistent nausea, vomiting, abdominal pain, or kidney diseases.

For children and the elderly, Miralax should be administered with caution as they are more vulnerable to its side effects.

Before you start taking it, contact your healthcare provider.

How much Miralax should I take for a bowel prep before a colonoscopy?

When you prepare for your colonoscopy, the bowel preparation solutions will be consumed in two parts. Follow these instructions:

Mix ½ a packet of Miralax (119 grams) in each 32-ounce Gatorade (not red) bottle until dissolved.

On the evening of the day before your colonoscopy, at 5.00 PM, take four Dulcolax tablets. After an hour, at 6.00 PM start drinking the mixed solution. Drink an 8-ounce glass of bowel preparation every 15 minutes for a total of four glasses.

Once the mixed solution is fully consumed, continue drinking a clear liquid diet at regular intervals till midnight.

For further reading, have look at other colon cleansers that aid weight loss such as Metamucil, Psyllium husk, and salt water flush in other articles here.