Is Weight Gain a Side Effect of Linzess?

If you have irritable bowel syndrome (IBS) or chronic idiopathic constipation (CIC), you may experience long bouts of constipation that are not only uncomfortable but also bad for your overall health.

In case your constipation fails to improve with other drugs, your doctor may resort to LINZESS, which is a constipation-relieving drug. You may have heard people talking about the ability of LINZESS to cause weight gain as a side effect.

If you’re wondering how LINZESS can affect your weight, this article will help you understand the drug, its uses, and side effects better and allow you to have a more detailed discussion with your doctor. In the end, you’ll be able to make a more informed choice about LINZESS.

What is LINZESS?

LINZESS is the brand name for a drug called linaclotide, which is used to treat constipation caused by IBS-C and CIC. LINZESS is also sometimes used off-label to treat opioid-induced constipation and ulcerative colitis.

At a biochemical level, LINZESS binds and activates a molecule called guanylate cyclase inside the cells of your gut. Activation of this molecule causes opening of chloride and bicarbonate channels, both of which diffuse out of the cell.

As chloride enters the gut lumen, it is followed by water. This leads to increased water content inside the gut, which makes the stool softer and improves its consistency. Soft stool passes along the gut easily, which treats constipation.

Can LINZESS make you gain weight?

Yes, there have been reports of weight gain with LINZESS use. But there have also been reports of weight loss with the drug, so its effect on weight is not clearly understood.

If you feel your weight has changed significantly since you started LINZESS, it's best to report this to your doctor. Your doctor may be able to give you a suitable alternative with fewer side effects than LINZESS.

How do you take LINZESS for weight loss?

You should not use LINZESS for weight loss. LINZESS has not been approved for weight loss and there’s no data on its efficacy, safety, and side effects when used as a weight loss drug.

However, other drugs — like orlistat — have been approved for weight loss and it’s a good idea to discuss them with your doctor. Exercise and dietary modifications are risk-free ways to lose weight, so you may want to try them before turning to drugs or surgery.

Who should not take LINZESS?

LINZESS should not be used by anyone who doesn’t have long-term constipation that does not respond to other drugs.

Even if you have long-term constipation, you should not use LINZESS unless prescribed by a doctor. LINZESS has a long list of drug interactions and may lead to dangerous side effects when combined with other drugs. If you’re already taking medications for other conditions, it becomes even more important to consult a doctor before starting LINZESS.

LINZESS is contraindicated in patients younger than 6 years. In these patients, the drug may lead to severe diarrhea and life-threatening dehydration. Doctors also don’t recommend LINZESS for patients under 18 because its safety and efficacy has not been clearly demonstrated in this group.

Should you drink a lot of water with LINZESS?

You should drink 7-8 glasses of water per day with LINZESS. This is true even if you’re not taking the drug. Your water requirement may go up if you experience diarrhea with LINZESS, which is a known side effect of the drug.

How to use LINZESS?

LINZESS should be taken by mouth30 minutes before the first meal of the day. It’s usually prescribed once daily.

It’s important to take the drug with water and on an empty stomach because it can cause unpleasant side effects like bloating and stomach pain if taken with food.

Some people find it difficult to swallow capsules. In that case, you can open up a LINZESS capsule and dissolve its contents in either:

● applesauce (one teaspoon) OR
● water (30 milliliters)

Make sure to swirl the mixture properly before drinking it. Don’t try to chew on the mixture or save it for future use.

The dosage and duration of your LINZESS course will be decided by a doctor and depends on why you’re taking it, your overall health, and any other medications that you use. You should know that LINZESS will not immediately relieve your constipation — it’s not a laxative and takes around 1 week to work.

What are the side effects of LINZESS?

Side effects of LINZESS include diarrhea, bloating, abdominal pain, gas, and severe allergic reaction.

The drug is generally safe and side effects usually mild, if any. The most common side effect is diarrhea.

In some cases, LINZESS may cause severe diarrhea, which requires urgent medical attention. Rarely, the drug may also lead to severe allergic reactions. If you experience any of the following signs after taking LINZESS, rush to a hospital immediately:

● Difficulty breathing
● Swelling around the face
● Severe itching
● Rash
● Dizziness

LINZESS is also known to interact with other drugs and alter their levels. This may lead to a wide range of side effects depending upon the exact combination of drugs you’re taking. Examples of drugs LINZESS can interact with include:

● Magnesium hydroxide, which is often used as a laxative
● Levothyroxine, which is used in patients with low thyroid levels
● Omeprazole, a proton-pump inhibitor used to reduce stomach acid secretion in heartburn patients
● Bisacodyl and psyllium, both of which treat constipation
● Pramlintide, an amylin analog used in diabetes mellitus

Also, if you have a history of intestinal obstruction, make sure your doctor knows it before prescribing LINZESS. The effect of LINZESS during pregnancy and breastfeeding is unclear. It should only be used when absolutely needed during pregnancy.


LINZESS works by increasing fluid secretion in the intestines and makes it easy for stools to pass out of the body. It’s mainly used for constipation due to IBS-C and CIC.

Weight gain and loss have both been reported with LINZESS. However, LINZESS is not a weight-loss drug. If you experience significant weight changes after starting LINZESS, you should report them to your doctor.

Medically Reviewed by Onikepe Adegbola, MD PhD

Back to blog

You might want to check

1 of 12