Does my medication cause constipation?

Written by Shivam Patel, PharmD, BSPS, RPh | Posted February 26, 2020 | Updated March 16, 2023

Constipation isn’t exactly dinner table conversation, yet it’s something almost everyone faces at some point or another. The fact is that sometimes our stubborn bowels just don't move, despite our straining and pushing… which usually results in anger and searching our memory to understand why this may be happening. We begin to ask ourselves questions like “Was it something I ate?”; “Am I stressed out about tax season?”; “Is it that new pill I started taking?”. There are many causes of constipation, but often times the suffering can be linked to medication. We can all have occasional disturbances in our bowel movements. When people have three or less bowel movements a week, medical experts usually define it as constipation.

What medications are constipation culprits?

  • Opioids, such as Oxycontin, Percocet, Vicodin, and Tylenol #3, are a class of medications prescribed to alleviate major pain. The most common problem associated with them is the threat of addiction, but there’s another one. They often cause constipation. It is also not uncommon to vomit or feel nauseated while taking these medications. Opioids work by depressing your central nervous system and activating opioid receptors in your body to block pain. The downside here is that many of these receptors are located in your gut. So, when they are activated, the way food moves through your digestive system slows down and fluid decreases in your intestines, causing constipation.

  • Non-steroidal anti-inflammatory drugs (NSAIDs), including Advil, Motrin and Aleve, are commonly used for pain and swelling as they are available over-the-counter (OTC). These medications are effective and work fast when you are in pain, however they also come with side effects of discomfort in your gut and constipation. NSAIDs cause constipation because they slow down movement in your gut and reduce muscle activity that would push digested food through the bowel.

  • Antidepressants, such as Prozac, Elavil, and Pamelor, are used to stabilize mood. They can also cause constipation because they work in the part of the brain that controls nerve endings in the digestive tract.

  • Allergy medications like Benadryl, Allegra, Claritin, and Zyrtec are all anticholinergics. They, of course, are used to treat annoying allergy symptoms, but also annoyingly they often cause dry mouth and constipation. Anticholinergics block a chemical called acetylcholine in your body, which reduces muscle movement in your digestive system resulting in constipation.

  • Urinary incontinence medications, such as Detrol and Ditropan, help when patients are having difficulty urinating, but they are also anticholinergics, which can cause constipation.

  • Blood pressure medications, which include beta blockers and calcium channel blockers like atenolol, verapamil, and diltiazem, all treat high blood pressure but also have a diuretic effect. Your body can become dehydrated and stool can become less moist resulting in constipation.

  • Nausea medications, like Zofran, are effective to prevent vomiting and nausea post surgery or chemotherapy, however these meds block a chemical in your body called serotonin which can result in constipation.

  • Iron supplements help treat an iron deficiency. Whether taken as supplements or in a multivitamin, they have common side effects including gas, upset stomach and constipation. Your body is not the best at absorbing iron, and excess is sent to the large intestine which results in constipation. It is best to start with low doses. Look for ferric iron, which is easier to digest in your body.

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For Constipation, Try Lifestyle Changes Before Looking to the Pharmacy

Constipation leads to frustration, I know. Before rushing to your local pharmacy looking for the most immediate relief, I recommend trying to find the source of constipation first. If you think it is caused by a medication you’re taking, work with your doctor, NP or other health care provider to see if there is the possibility of changing your dose or timing that can help. I also recommend a close eye on specific lifestyle changes.

You need to make sure you are eating enough fiber every single day. Fruits and vegetables are easy to forget, but they are your friend if you wish to alleviate constipation.

You also need to make sure you are drinking enough water every day (8 x 8oz glasses minimum). How many glasses have you had so far today? Go drink some water!

Last but equally as important as all the above, make sure you are exercising routinely. Exercise moves food through your large intestine faster, reducing your chances of getting backed up. So get moving!

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What is the best OTC laxative for constipation?

The above natural ways to beat constipation will not always work and the next step could be laxatives at the pharmacy. Like prescription medications, the effectiveness of laxatives varies from person to person. You will have to try for yourself to see what makes you have a successful bowel movement. When you walk through the laxative aisle at your local pharmacy, it may seem confusing with all the options. Below, I break down what could work best for you.

Laxative Comparisons

Laxative Type Common Generic/ Brand Names How does it work? When can I expect a bowel movement? Can I use it long term?
Oral Stool Softeners Docusate Sodium (Colace, Surfak) Brings in moisture to stool allowing for less strain during bowel movement 24 - 72 hours Yes
Oral Stimulants Senna (Senokot) Bisacodyl (Dulcolax) Activates gut muscles to help push out stool 6 - 10 hours No
Oral Osmotics Magnesium Hydroxide (Miralax, Phillips Milk of Magnesia) Brings water into colon allowing stool to pass easier Less than 30 minutes Yes
Oral Bulk Formers Psyllium (metamucil) Calcium polycarbophil (FiberCon) Forms bulky stool with water absorption allowing gut muscles to work naturally 48 - 72 hours Yes
Rectal Suppositories Bisacodyl (Dulcolax) Glycerin (Pedia-Lax) Activates gut muscles to help soften stool 15 - 60 minutes No
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What is the best prescription medication for constipation? How can I save money?

At this point, you have tried everything above yet are still suffering from constipation. Lifestyle changes and OTC products didn’t cut it, so it's time to discuss prescription options with your provider. These medications are proven to be effective at treating constipation and are generally good for long term use as well:

  • Lubiprostone (brand name Amitiza) works by bringing more fluid into the digestive tract, which allows stools to pass smoothly. It is used to treat chronic constipation and irritable bowel syndrome with constipation in adults. There is currently no generic version of this medication available in the U.S. You can find 60 capsules of 24mcg generic Amitiza at PharmacyChecker-accredited international online pharmacies at an 85% discount compared to $474.50, the average U.S. retail price of Amitiza.

  • Plecanatide (Trulance) works by increasing the way food and waste move through your digestive tract. It is also used to treat chronic constipation and irritable bowel syndrome with constipation in adults. There is currently no generic version of this medication available. However, you can still find savings on the brand at U.S. pharmacies using the U.S. Prescription Discount Card. The lowest cost for 30 tablets of Trulance in ZIP Code 10605 would be $438.80 compared to the average retail price of $497.60, around a 12% savings.

  • Linaclotide (Linzess) works in the same way as Trulance, allowing food to move efficiently through your intestines. It is used to treat chronic constipation and irritable bowel syndrome with constipation in adults. There is currently no generic version of this medication. Don’t worry-- there is still a way you can save money. The average U.S. retail price of 30 capsules of 145mcg Linzess is $517.59. You can find Linzess at PharmacyChecker-accredited international online pharmacies for $152.99-- that’s a 70% savings.

  • Methylnaltrexone (Relistor) helps treat opioid-induced constipation by blocking the effect opioid medications have on your intestines and gut. There is currently no generic version of this medication available. You can save money using the U.S. Prescription Discount Card at U.S. pharmacies.

  • Naldemedine (Symproic) works similarly to Relistor by blocking opioid medications from binding to receptors in your gut. There is currently no generic version of this medication available. The average U.S. retail price of 30 tablets of Symproic 0.2mg is $426.20. With the U.S. Prescription Discount Card, you can pay as low as $378.91. That's an 11% savings.

  • Naloxegol (Movantik) works to treat opioid induced constipation in the same way as Relistor and Symproic. It prevents opioid medications from binding to receptors in your gut that would usually make you constipated, and, I would say, pretty unhappy. There is currently no generic version of this medication in the U.S. However, you can save money on a brand version at PharmacyChecker-accredited international online pharmacies. The average U.S. retail price of 30 tablets of Movantik 25mg is $450.27. You can find Movantik at PharmacyChecker-accredited international online pharmacies for $208.99-- that's around a 54% savings.

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Where are prescription constipation medications made?

A U.S. Relistor manufacturer label shows that it is made in Canada by Patheon Inc for Salix Pharmaceuticals.

relistor drug label

A U.S. Movantik manufacturers label shows that it is made by AstraZeneca AB Sweden for AstraZeneca Pharmaceuticals LP.

movantik label

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