Tremfya (guselkumab) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it to treat moderate to severe plaque psoriasis and active psoriatic arthritis in certain adults. Tremfya is used as a long-term treatment.

Here are some fast facts about Tremfya:

  • Active ingredient: guselkumab, which is a biologic
  • Drug class: interleukin-23 blocker
  • Drug form: solution that’s given by subcutaneous injection
  • FDA approval year: 2017

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

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

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

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

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

Mild side effects that have been reported with Tremfya include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer, bother you, or become severe, 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 Tremfya and want to tell the FDA about it, visit MedWatch.

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

Tremfya may cause serious side effects. Serious side effects are rare, so it is important to know common warning signs. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Tremfya’s prescribing information.

If you develop serious side effects while taking Tremfya, 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 and their symptoms include:

* For more information about this side effect, see “Side effect specifics” below.
† An allergic reaction is possible after using Tremfya. However, this side effect wasn’t reported in clinical trials. To learn more, see the “Side effect specifics” section below.

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

Does Tremfya cause long-term side effects?

Yes, it is possible to develop long-term side effects from Tremfya.

In clinical trials, infection occurred in some people taking the drug. Infections can occur right after starting Tremfya or at any time during treatment. This is because Tremfya can lower the activity of the immune system, which could make it harder for the body to fight off infections.

The most common infections reported in clinical trials were:

These infections were mild to moderate in severity. Depending on the severity of the infection, your doctor may wait until the infection clears before starting or continuing Tremfya therapy.

If you have symptoms of an infection while taking Tremfya, make sure to talk with your doctor. They can evaluate your symptoms, order tests to check for infection, and recommend treatment options. Your doctor will advise whether you need to stop taking Tremfya while your body recovers from the infection.

Can Tremfya cause cancer as a side effect?

It is not likely that Tremfya causes cancer. Cancer was not reported as a side effect of Tremfya in clinical trials.

One study looking at Tremfya treatment showed that people rarely developed cancer during treatment. Another study had similar results. However, the exact cause of the cancer and whether it was due to Tremfya was unclear.

Other medications used to treat psoriatic arthritis and plaque psoriasis have been shown to increase the risk of cancer. Examples include ustekinumab (Stelara) and adalimumab (Humira). Even though these medications are similar to Tremfya, they do not share the exact same side effects.

If you’d like to know more about the risk of cancer with certain treatments, talk with your doctor.

Is weight gain a side effect of Tremfya treatment?

No, weight gain has not been shown to be a side effect of Tremfya.

On the other hand, infections can cause sudden weight loss. And Tremfya can increase the risk of infections, including tuberculosis, which can cause severe weight loss.

If you experience weight loss while taking Tremfya, talk with your doctor or pharmacist. They can check to see what may be causing your weight loss and help you maintain a body weight that’s healthy for you.

Should I expect hair loss during treatment with Tremfya?

Hair loss was not reported as a side effect of Tremfya in clinical trials.

That said, keep in mind that Tremfya is used to treat different types of plaque psoriasis, including scalp psoriasis. Hair loss is very common in people with scalp psoriasis, and it may be confused as a side effect of Tremfya.

If you experience hair loss while taking Tremfya, talk with your doctor. They may be able to recommend ways to help manage your hair loss.

Could I develop depression while using Tremfya?

Depression was not reported as a side effect of Tremfya in clinical trials.

Depression is a condition that has many different causes. While it is possible to develop depression while taking Tremfya, the exact cause could be related to something else. Plaque psoriasis or psoriatic arthritis are examples of conditions that may cause depression, depending on how severe they are. And Tremfya is used to treat each of these conditions.

If you have any symptoms of depression while taking Tremfya, it’s important to talk with your doctor. They can suggest ways to help manage your symptoms.

Learn more about some of the side effects that Tremfya may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Tremfya.

Reaction at the injection site

You will administer doses of Tremfya as a subcutaneous injection. There may be some irritation around the injection site.

Symptoms of an injection site reaction include:

  • redness or deepening skin color
  • bruising
  • pain
  • itching
  • swelling

Injection site reaction was uncommon in the drug’s clinical trials.

What you can do

Try these strategies to help prevent injection site reactions:

  • Rotate the injection site to decrease the risk of irritating one area.
  • Thoroughly clean the injection site before giving yourself an injection.
  • Use the proper technique for injecting Tremfya. Ask your doctor or healthcare professional to give you feedback after they watch you administer an injection.

If you experience injection site reactions often, or the symptoms are bothersome, talk with your doctor or pharmacist. They can suggest ways to help manage your symptoms.

Infection

Infection was a common side effect of Tremfya in clinical trials. This medication can lower the activity of the immune system, which could make it harder for the body to fight off infections.

Symptoms of an infection can include:

  • fever
  • weight loss
  • tiredness
  • headache
  • nausea
  • achiness
  • cough
  • chills
  • sweating

The most common infections reported in Tremfya’s clinical trials were:

While these infections are common with Tremfya, they are typically mild or moderate. And they should not lead to having to stop treatment with the drug.

What you can do

To reduce the risk of infection anytime — but especially while taking Tremfya — it is important to:

  • Stay up to date on your vaccinations, including the annual flu vaccine.
  • Practice healthy hygiene habits, such as washing your hands frequently.
  • Fully cook meat to help prevent foodborne illness.

If you experience symptoms of an infection, talk with your doctor right away. They can evaluate your symptoms and may order tests to check for infection. They may also prescribe medication to treat the infection.

The type of medication depends on the type of infection and may include antibiotics, antifungals, or antiviral medications. Your doctor will also advise whether you need to stop taking Tremfya while your body recovers from the infection.

Tuberculosis

Tremfya can lower the activity of your immune system and increase your risk of developing tuberculosis (TB). TB is an infection that typically affects the lungs.

New TB infections were not reported in Tremfya’s clinical trials. However, Tremfya can cause TB to reactivate. With reactivation, TB that’s already inside the body becomes active again and causes symptoms.

Symptoms of TB include:

What you can do

If you’ve had TB, it’s important to tell your doctor before starting Tremfya. This will help your doctor assess your risk of reactivated TB. Your doctor may also prescribe medication to treat or help prevent TB before you start taking Tremfya.

Your doctor will likely recommend testing for TB before prescribing Tremfya. This is true even if you have never had TB. Your doctor will also monitor for symptoms of TB while you are taking Tremfya.

If you have symptoms of TB while taking Tremfya, tell your doctor immediately. If reactivation of TB occurs, your doctor will likely pause Tremfya until your TB has been treated. Or your doctor may stop your Tremfya treatment and recommend another treatment option for plaque psoriasis or active psoriatic arthritis.

Headache

Headache is a possible side effect of Tremfya. However, this side effect was not commonly reported in the drug’s clinical trials. Frequent mild headaches can impact the quality of your daily life. It’s important to note that several different factors can cause headaches.

What you can do

Talk with your doctor if you are experiencing frequent headaches or bothersome headaches while using Tremfya. Your doctor may recommend additional rest and over-the-counter pain relief medications, such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin).

Allergic reaction

Similar to other drugs and biologics, Tremfya can cause an allergic reaction in some people. However, this side effect wasn’t reported in clinical trials. There have been some reports of Tremfya causing an allergic reaction after the drug was approved, but it is not clear how often this has happened or if Tremfya was the cause.

Symptoms of an allergic reaction can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • 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 to continue treatment with Tremfya or stop taking it. However, 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 Tremfya. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health. These are considered drug-condition or drug-factor interactions. The conditions and factors to consider include:

Allergic reaction. If you’ve had an allergic reaction to Tremfya or any of its ingredients, your doctor will likely not prescribe Tremfya. Ask your doctor what other medications may be better options for you.

Tuberculosis (TB). If you’ve had TB, it may need to be treated before you start Tremfya. This helps to prevent worsening TB with Tremfya treatment. Your doctor will test for TB before you start Tremfya. They will also monitor for symptoms of TB, such as extreme tiredness or cough, while you are taking Tremfya.

Infection. Tremfya may weaken your immune system and increase your risk of developing an infection. If you have any infections prior to taking Tremfya, your doctor may treat the infection and wait for the infection to clear before starting Tremfya. If you develop symptoms of an infection while taking Tremfya, tell your doctor immediately.

Pregnancy/Breastfeeding. It’s not known whether Tremfya is safe to take during pregnancy or while breastfeeding. For more information, please see the “Pregnancy and breastfeeding while taking Tremfya” section.

Alcohol with Tremfya

There is no known interaction between Tremfya and alcohol.

That said,alcohol may increase swelling and inflammation in your body, which can worsen plaque psoriasis or psoriatic arthritis. (Tremfya is used to treat both of these conditions.)

Additionally, alcohol may decrease your body’s ability to fight off infection, increasing your risk of serious infection with Tremfya.

If you consume alcohol, talk with your doctor prior to starting Tremfya treatment.

Pregnancy and breastfeeding while taking Tremfya

It’s not known whether it’s safe to take Tremfya during pregnancy or while breastfeeding. There are no clinical trials in humans assessing the drug’s use during these times.

However, it’s known that certain antibodies (immune system proteins) can cross the placenta. This could mean Tremfya may be able to pass from a pregnant person to a fetus.

If you’re pregnant, able to become pregnant, or breastfeeding, talk with your doctor before starting Tremfya. Your doctor will advise you on the risks and benefits of Tremfya treatment. If you become pregnant while taking Tremfya, consider enrolling in the drug’s pregnancy registry by calling 877-311-8972.

Side effects are possible when taking Tremfya for plaque psoriasis or psoriatic arthritis. Most side effects are typically mild to moderate in severity. If you experience any severe side effects, it is important to talk with your doctor right away. For more information, see the sections above.

If you’d like to learn more about Tremfya, 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:

  • More information about Tremfya. For details about other aspects of Tremfya, refer to this article.
  • Drug comparison. Learn how Tremfya compares with Stelara and Humira.
  • Dosage. For information about the dosage of Tremfya, view this article.
  • Cost. To find out about Tremfya and cost, see this article.
  • A look at your condition. For details about plaque psoriasis, see our psoriasis or dermatology hubs. You can view our arthritis hub for information about psoriatic arthritis.

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.