Cosentyx (secukinumab) is a prescription brand-name medication. It’s approved by the Food and Drug Administration (FDA) to treat the following conditions:

For plaque psoriasis treatment, Cosentyx can be used in adults as well as children ages 6 years and older. For treating the other conditions it’s approved for, Cosentyx can be used in adults.

If you and your doctor agree that Cosentyx is working to treat your condition, you’ll likely use the drug long term.

Here are some fast facts on Cosentyx:

  • Active ingredient: secukinumab, which is a biologic
  • Drug class: monoclonal antibody
  • Drug forms: liquid solution for subcutaneous injection, and powder that’s made into a liquid solution for subcutaneous injection

Like other drugs, Cosentyx injections can cause side effects. Read on to learn about potential common, mild, and serious side effects. For a general overview of Cosentyx, including details about its uses, see this article.

Cosentyx can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days or weeks. But if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who used Cosentyx in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Cosentyx use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Cosentyx’s medication guide.

Mild side effects that have been reported with Cosentyx include:

These side effects may be temporary, lasting a few days or weeks. But if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks side effects of the medication. If you develop a side effect while taking Cosentyx and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.

Cosentyx may cause serious side effects, including some long-term side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Cosentyx’s medication guide.

If you develop serious side effects while taking Cosentyx, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects* that have been reported include:

* For more information about these side effects, see “Side effect specifics” below.

Cosentyx may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Are there any rare side effects of Cosentyx?

Yes, Cosentyx can cause some rare side effects, such as:

For details about how often these side effects occurred, see Cosentyx’s prescribing information.

* For more information about this side effect, see “Side effect specifics” below.

Is weight loss a side effect of Cosentyx?

No, weight loss isn’t a side effect of Cosentyx. But weight loss can be a symptom of some rare but serious side effects* from Cosentyx, including:

Another drug used to treat psoriatic arthritis and plaque psoriasis, called Otezla (apremilast), commonly causes weight loss as a side effect.

If you have unexplained weight loss along with other symptoms of these side effects, contact your doctor. They’ll likely want to see you to evaluate your symptoms. If you have other questions about your weight while taking Cosentyx, talk with your doctor or pharmacist.

* For more information about these side effects, see “Side effect specifics” below.

Can taking Cosentyx cause fatigue?

No, fatigue (lack of energy) isn’t a known side effect of Cosentyx. This wasn’t reported in clinical trials of the medication.

Fatigue can be a side effect of some other drugs used to treat plaque psoriasis and psoriatic arthritis, such as Stelara (ustekinumab). Fatigue can also be a side effect of inflammatory bowel disease, which is a rare side effect of Cosentyx. (See “Side effect specifics” below for details about this side effect.)

If you have concerns about fatigue, talk with your doctor. They can suggest ways to help improve your energy levels.

Does Cosentyx cause depression?

No, depression isn’t a known side effect of Cosentyx. This wasn’t reported by people taking the drug in clinical trials. Depression can be a side effect of some other drugs used to treat plaque psoriasis, such as Siliq (brodalumab), though.

If you have questions or concerns about your mood or depression while using Cosentyx, talk with your doctor. They can help evaluate your symptoms and determine the best treatment for you.

Can Cosentyx cause hair loss?

No, Cosentyx isn’t known to cause hair loss. This wasn’t reported in clinical trials of the drug.

Some people with plaque psoriasis experience hair loss as a symptom. This can happen due to itching and irritation that affects your hair roots. Hair loss due to plaque psoriasis typically isn’t permanent.

If you’re concerned about hair loss, talk with your doctor. They can help determine the cause and suggest safe treatments for you.

Learn more about some of the side effects that Cosentyx may cause.

Skin rash

A rash or hives (raised, itchy, and red or discolored patches of skin) are possible side effects of Cosentyx. These side effects were rare in clinical trials of the drug.

It’s possible for a rash or hives to be a sign of an allergic reaction to Cosentyx, which can be severe. See “Allergic reaction” below for details.

What you can do

If you’re experiencing a rash or hives along with other symptoms of an allergic reaction, call your doctor right away. If your symptoms feel life threatening, get emergency medical help immediately (call 911 or go to your closest emergency room).

If you develop a rash or hives without other symptoms, call your doctor. They can help determine if you’re having a reaction to Cosentyx. They may recommend ways to treat your rash. They can also determine whether it’s safe for you to continue treatment with Cosentyx.

Headache

Headache is a possible side effect of Cosentyx. Only people using Cosentyx to treat psoriatic arthritis reported headache in clinical trials. This side effect wasn’t reported by people using Cosentyx to treat the other conditions it’s prescribed for.

What you can do

Call your doctor if you experience headache while taking Cosentyx. They can help determine if there are other possible causes of your headache. They may also recommend headache treatments such as over-the-counter pain relievers such as Tylenol (acetaminophen).

Inflammatory bowel disease

Although rare, Cosentyx can cause inflammatory bowel disease (IBD). IBD refers to a group of conditions that cause damage and swelling in your digestive tract. The two most common types of IBD are ulcerative colitis and Crohn’s disease.

Symptoms of IBD can include:

  • diarrhea
  • difficult or incomplete bowel movements
  • fatigue (lack of energy)
  • stomach pain
  • weight loss

Cosentyx can also make IBD worse in people who already have it. This is called an exacerbation. In rare cases, exacerbations caused by Cosentyx can be serious.

What you can do

If you already have IBD, be sure your doctor is aware of this before you begin using Cosentyx. They can help determine whether Cosentyx is safe for you to use.

If you develop new symptoms of IBD while using Cosentyx, call your doctor. They can evaluate your symptoms and help figure out whether they’re caused by Cosentyx. They can also help determine whether you should keep using Cosentyx, or if another treatment for your condition should be considered.

Infections

Infections are a possible side effect of Cosentyx. This is because Cosentyx works by reducing the activity of your immune system, which can make it harder for your body to fight infections.

Infections were rare in clinical trials of Cosentyx, but they can be serious. Some people in trials reported severe respiratory infections, including bronchitis (a type of lung infection) and candidiasis (a fungal infection). Mild infections, such as nasopharyngitis (also known as the common cold), are also possible.

Symptoms of an infection can vary. Some general symptoms include:

  • diarrhea
  • fever
  • stuffy nose
  • throat pain
  • tiredness

Note: If you’ve had tuberculosis (TB) in the past, it’s possible for Cosentyx to “activate” a TB infection that’s been latent (not causing symptoms). TB is a lung disease that can remain in your body for a long time without causing symptoms. Your doctor will test you for TB before you start using Cosentyx. If your result is positive, your doctor will treat your TB before you start Cosentyx. They’ll also monitor you for any TB symptoms while you use Cosentyx.

What you can do

If you develop infection symptoms while taking Cosentyx, contact your doctor. They’ll likely want to see you to determine the cause of your symptoms. They may recommend treatment, such as an antibiotic or antifungal medication. They can also help determine whether it’s safe for you to keep using Cosentyx.

Most people who develop a mild infection are able to keep using Cosentyx. But if your infection is serious, your doctor may have you stop taking the medication and try another treatment for your condition.

You’ll also need to avoid live vaccines while taking Cosentyx. This is because live vaccines contain a weakened form of the bacteria or virus they protect against. Normally, live vaccines don’t cause sickness in people with healthy immune systems. Because Cosentyx weakens your immune system, your body may not be able to fight the bacteria or virus in the vaccine like it usually would.

Examples of live vaccines to avoid while using Cosentyx include the chickenpox vaccine, the intranasal flu vaccine, and the measles, mumps, rubella (MMR) vaccine.

Allergic reaction

As with most drugs, Cosentyx can cause an allergic reaction in some people.

Symptoms can be mild or serious and can include:

  • rash or hives
  • itching
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, typically in your lips, eyelids, feet, or hands
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Cosentyx. But if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Be sure to talk with your doctor about your health history before you take Cosentyx. This drug may not be the right treatment for your condition if you have certain other medical conditions or factors that affect your health. The conditions and factors to consider include:

Chronic infections, including tuberculosis (TB). Cosentyx weakens your immune system and increases your risk for infections. If you have an infection, you’ll need to have it treated before you start taking Cosentyx. Cosentyx can also activate TB that’s latent (present in your body but not currently causing symptoms).

Your doctor will test you for TB before you start Cosentyx treatment. If your test result is positive, you’ll need to have the infection treated before you can safely start using Cosentyx. If you have a history of chronic infections, be sure to let your doctor know. They can help determine whether Cosentyx is a safe choice for you.

Inflammatory bowel disease (IBD). If you have IBD, taking Cosentyx could make it worse. Be sure to discuss this with your doctor before you start using Cosentyx. They may want to monitor your IBD closely during Cosentyx treatment. Or, they may decide to try a different treatment for your condition.

Allergic reaction or latex allergy. You shouldn’t take Cosentyx if you’ve ever had an allergic reaction to Cosentyx or any of its ingredients. And if you have a latex allergy, talk with your doctor about this. Cosentyx pens and syringes may have caps that contain latex, so you may need a latex-free syringe for Cosentyx injections.

Alcohol use with Cosentyx

There aren’t any known interactions between alcohol and Cosentyx. That being said, if you have plaque psoriasis, drinking alcohol could lower your chance of responding to treatment.

Also, alcohol does interact with a drug called methotrexate (Trexall, Rasuvo, RediTrex, Otrexup). This drug is sometimes prescribed with Cosentyx for psoriatic arthritis treatment. Taking alcohol with methotrexate can result in severe liver problems.

If you drink alcohol, it’s best to talk with your doctor before you start using Cosentyx. They can recommend how much alcohol, if any, is safe for you during treatment.

Pregnancy and breastfeeding while taking Cosentyx

It’s not known if Cosentyx is safe to take while pregnant. There isn’t enough data about the drug’s use during pregnancy to know what effects it may have. Talk with your doctor about safe ways to treat your condition while pregnant.

It’s also not known whether Cosentyx is safe to take while breastfeeding. So if you’re currently breastfeeding or planning to breastfeed, talk with your doctor about safe ways to feed your child while taking Cosentyx.

Side effects of Cosentyx can occur, but they aren’t common. Most mild side effects of the drug go away with time and don’t require medical attention.

You should talk with your doctor if you experience symptoms of serious side effects, including:

These side effects could be serious and require medical attention. Also, if you become pregnant while you’re using Cosentyx, talk with your doctor. It isn’t known if the drug is safe to take while pregnant.

If you’d like to learn more about Cosentyx, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.