How Long Does It Take For Miralax To Work?

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

Symptoms of severe constipation, such as cramping and abdominal pain, bloating, gas, and bowel movement trouble, are 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 a fast result.

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 helpful, but its effectiveness and speed depend on several factors. In the rest of this article, you’ll read all the relevant facts that every supplement user should know.

Uses and Benefits of Miralax

Miralax is an osmotic laxative used to treat 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 that you mix with 4 to 8 ounces of liquid and drink.

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 bloating, constipation, and stomach cramps.

Miralax can be used for bowel evacuation before a colonoscopy and relieve occasional constipation. It is also used as a colon-cleansing supplement.

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

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

Since then, Miralax has been the most popular anti-constipation medication thousands of people use worldwide. Polyethylene glycol 3350 is sold under several brand names. The “3350” qualifier refers to this particular PEG variant’s molecular weight.

Talk with your doctor before using Miralax and follow the colonoscopy bowel prep instructions.

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 within 1–3 days of use.

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

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

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

Miralax Benefits And Results

Frequently Asked Questions 

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, resulting in the stool loosening. 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 restroom, so you can use it without fear that it might interrupt your day.

Store it at room temperature, away from moisture and heat.

How do I use Miralax?

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

Take the recommended dose of this laxative in powder form using the bottle cap. On the cap’s inside, lines indicate the amount of powder to be used per 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.

You can take one dose of Miralax at any time of the day for up to 7 days.

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 with large volumes of water.  A doctor may prescribe a different dosage depending on your condition.

What is the dose of Miralax for children?

There have been a lot of discussions about 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 their bowel movements without harsh side effects.

However, Miralax overdoses or regular use of it for an extended period may cause 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 discomfort 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 the rash-affected area,
  • Severe dizziness,
  • Breathing difficulties.

Generally, Miralax doesn’t produce any serious side effects. The ingredients 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 interactions?

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

When your doctor recommends it, you should inform the doctor of any other prescription medicines you use.

Be sure to follow the instructions of your doctor or pharmacist when taking other medications as well.

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

What are the diet modifications required for fast results?

Patients suffering from constipation need to eat at least 25 grams of soluble fiber daily. Some of the most 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 daily to prevent constipation.

Avoid eating certain foods that have a reputation for being “binding” or constipating. Some 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 an hour is necessary to relieve constipation quickly.

Can anyone use Miralax?

If you are allergic to polyethylene glycol, this anti-constipation medication is not for you.

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 specific intestinal or stomach problems like bowel obstruction or others shouldn’t take Miralax.

Do not use this medication for health issues such as persistent nausea, vomiting, abdominal pain, or kidney disease.

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?

The bowel preparation solutions will be consumed in two parts when you prepare for your colonoscopy. 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 p.m., take four Dulcolax tablets. After an hour, at 6 p.m., 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 until midnight.

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