Does Cymbalta cause constipation?

Constipation is uncomfortable — sometimes even painful. It is also a very common condition. About 16% of people in the United States live with chronic constipation. Constipation has many causes, ranging from lifestyle factors to underlying medical conditions. Constipation is also a common side effect of many medications—including antidepressants like Cymbalta. Other common Cymbalta side effects include nausea, drowsiness, and dry mouth.

Cymbalta (duloxetine HCl) is a delayed-release serotonin-norepinephrine reuptake inhibitor (SNRI) used to treat mental health conditions such as major depressive disorder and generalized anxiety disorder. It is also prescribed to treat some chronic nerve or musculoskeletal pain disorders such as fibromyalgia or diabetic neuropathy. Duloxetine works by increasing both serotonin and norepinephrine levels, differentiating it from selective serotonin reuptake inhibitors (SSRIs) like Prozac (fluoxetine) and Paxil (paroxetine), which only increase serotonin. 

RELATED: Foods and drugs to avoid while taking Cymbalta

Does Cymbalta cause constipation?

Constipation is a common side effect of Cymbalta. In placebo-controlled clinical trials, about 10% of patients taking Cymbalta reported this reaction to the medication. Other common adverse effects included nausea, headache, dry mouth, and decreased appetite (which could lead to weight loss).

Of course, Cymbalta is not the only medication that causes constipation. Many antidepressants, especially tricyclic antidepressants like Elavil (amitriptyline), are linked with constipation. Paxil (paroxetine), an SSRI antidepressant, has been associated with the highest risk of constipation. 

Relationship between Cymbalta and constipation

Many antidepressants have “anticholinergic properties,” says Jodie Pepin, Pharm.D., the clinical pharmacy program director at Harbor Health. This means they block a neurotransmitter called acetylcholine, which plays a role in the body’s digestive fluid production and process of moving food through your intestines. Although Cymbalta has a minimal range of anticholinergic side effects, it may cause sluggish intestinal movement and dry stool, which may lead to constipation.

How long does Cymbalta constipation last?

Sometimes, side effects are temporary and subside as your body adjusts to the medication. Cymbalta constipation should resolve within a few days to a few weeks as your body adjusts to Cymbalta, according to Amy Lee, MD, chief medical officer of Lindora Clinic in California.

“The time frame is different for everyone,” Dr. Lee says. “But you can definitely prevent it by doing all you can to keep your stools soft!”

Management and treatment of Cymbalta-induced constipation

“Knowing that this medication could cause constipation, make sure you drink plenty of fluids when you are on the medication,” says Dr. Lee.

There are a number of specific strategies to help get rid of Cymbalta-related constipation:

• Stay hydrated. “The standard daily recommendation is about 2-3 liters,” says Dr. Lee, adding that good hydration also requires avoiding dehydrating substances such as alcohol and caffeine.
• Eat more fiber. Eating high-fiber fruits and vegetables can help ward off constipation. Dr. Pepin specifically recommends eating prunes or drinking prune juice.
• Try a stool softener. Stool softeners are over-the-counter medications that increase the water retained in stools so that it moves through the digestive system more smoothly. While stool softeners can provide relief, you may want to consult a healthcare provider before starting a new medication,
• As a last resort, try a laxative. “Natural laxatives called sennosides [are] milder than stimulant laxatives,” says Dr. Pepin. However, she cautions that even “natural” laxatives should not be used for longer than two weeks. 
• Work with your healthcare provider to find the correct dose. If you have side effects that do not go away or worsen, you may need a higher or lower dosage, even temporarily. Sometimes, healthcare professionals prescribe a smaller dose for the first week to help your body adjust to Cymbalta.

A word of caution from Pepin: While there are no specific negative drug interactions to consider, laxatives should be a last resort for Cymbala constipation. “A regular regimen of laxatives should be avoided,” Dr. Pepin says, adding that abusing laxatives can cause other problems and possible side effects, such as diarrhea, which could lead to dehydration. Young adults should also avoid laxatives since regular use can become a pattern that makes discontinuation difficult. 

When to see your healthcare provider

Constipation is a common side effect of Cymbalta. However, even common side effects can be serious. If untreated, constipation can lead to severe abdominal pain, hemorrhoids, anal fissures, and other gastrointestinal dysfunction.

“If constipation is intolerable, severe, or lasts an extensive period of time, a call to the prescriber is warranted in order to rule out any other possible cause,” says Dr. Pepin. “The medicine could be stopped or some treatment to relieve the constipation can be initiated.

Whether or not you are constipated, you should also tell your healthcare provider if you develop any of these serious side effects of Cymbalta, some of which are life-threatening:

• Suicidal thoughts, mania, or hypomania
• Serotonin syndrome
• Angle-closure glaucoma
• Seizures
• Low levels of salt or sodium in the blood (hyponatremia)
• Liver poisoning, which can lead to liver failure
• Dangerously high blood pressure
• Heart problems, such as fast heart rate or irregular heartbeat
• Sudden drop in blood pressure when changing from a sitting or lying position to a standing one (orthostatic hypotension), which may lead to fainting and falling
• Trouble urinating
• Severe allergic reactions or severe skin reactions
• Withdrawal symptoms after abruptly discontinuing the drug

When taken with warfarin or other blood thinners, SNRIs such as Cymbalta may cause an increased risk of internal bleeding. Always tell your healthcare provider about any medications or supplements you are taking so they can determine the most appropriate treatment options for your condition. 

If you have thoughts of suicide or self-harm, please seek help immediately. Go to your nearest emergency room or call a helpline such as the National Suicide Prevention Hotline. Never discontinue Cymbalta without talking to your provider first. Only a healthcare professional can give you medical advice specific to your situation.