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URL of this page: https://medlineplus.gov/druginfo/meds/a617036.html

Guselkumab Injection

pronounced as (gue" sel koo' mab)

Why is this medication prescribed?

Why is this medication prescribed? has been expanded.

Guselkumab injection is used to treat: moderate to severe

  • plaque psoriasis (a skin disease in which red, scaly patches form on some areas of the body)
  • psoriatic arthritis (a condition that causes joint pain and swelling and scales on the skin)
  • ulcerative colitis (a condition which causes swelling and sores in the lining of the colon [large intestine] and rectum)

Guselkumab injection is in a class of medications called called interleukin antagonists. It works by stopping the action of interleukin, a substance in the body that causes inflammation.

How should this medicine be used?

Guselkumab injection comes as a solution (liquid) in a prefilled pen and a one-press patient injector to inject subcutaneously (under the skin). It also comes as a solution to inject intravenously (into a vein). It is usually given every 4 to 8 weeks.

Use guselkumab injection exactly as directed. Ask your doctor or pharmacist to explain any part you do not understand. Do not take more or less of it or take it more often than prescribed by your doctor.

Yourr first dose of subcutaneous guselkumab injection will be given in your doctor's office. After that, you may be allowed to inject the medicine yourself. Or a caregiver may give it to you. Your healthcare provider will show you or your caregivers how to inject guselkumab. Read the written instructions that come with it before injecting your first dose.

Use each syringe or one press patient-controlled injector device only once and inject all the solution in the syringe. Discard the used syringe or device even if there is still some medication left in it. Dispose of used syringes or devices in a puncture-resistant container. Talk to your doctor or pharmacist about how to dispose of the puncture-resistant container.

Remove the prefilled syringe or one press patient-controlled injection device from the refrigerator and place on a flat surface without removing the needle cover or device cap. Allow it warm to room temperature for 30 minutes before injecting. Do not try to warm the medication by heating it in a microwave, placing it in hot water, leaving it in sunlight, or through any other method.

Do not shake a prefilled syringe or press patient-controlled injection device that contains guselkumab. Do not use if it is dropped; it has glass parts and should be handled carefully.

Always look at guselkumab solution before injecting it. Check that the expiration date has not passed and that the liquid is clear and colorless to slightly yellow. The liquid may contain a few small white particles or air bubbles. Do not use the prefilled syringe or device if it is damaged, expired, frozen, or if the liquid is cloudy, discolored, or contains large particles.

Inject within 5 minutes of removing the needle cover or device cap. Do not replace the needle cover or device cap as this can damage the needle or cause injury. Do not use an automatic injection device that has been dropped after removal of the device cap.

You can inject guselkumab injection anywhere on the front of your thighs (upper leg) or lower stomach area except your navel (belly button) and the area 2 inches (5 centimeters) around it. If someone else injects the medication, the back of the upper arm may also be used. Do not inject into an area where the skin is tender, bruised, red, hard, or scaly, or where you have scars or stretch marks.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before using guselkumab injection,

  • tell your doctor or pharmacist if you are allergic to this drug, any part of this drug, or any other drugs, foods or substances. Tell your doctor or pharmacist about the allergy and what symptoms you had.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while using guselkumab injection, call your doctor.
  • check with your doctor to see if you need to receive any vaccinations before beginning your treatment with guselkumab injection. Do not have any vaccinations during your treatment without talking to your doctor.
  • you should know that guselkumab injection may decrease your ability to fight infections and increase the risk that you will get an infection. Tell your doctor if you often get any type of infection or if you have or think you may have any type of infection now. This includes new or changing skin lesions, minor infections (such as open cuts or sores), infections that come and go (such as cold sores), and chronic infections that do not go away. If you experience any of the following symptoms during or shortly after your treatment with guselkumab injection, call your doctor immediately: sweating; chills; muscle aches; cough; shortness of breath; fever; weight loss; extreme tiredness; flu-like symptoms; vomiting; sore throat; runny, stuffed nose, or sneezing; warm, red, or painful skin; painful or frequent urination; diarrhea; stomach pain; or other signs of infection.
  • you should know that using guselkumab injection increases the risk that you will develop tuberculosis (TB; a serious lung infection), especially if you are already infected with tuberculosis but do not have any symptoms of the disease. Tell your doctor if you have or have ever had TB, if you have lived in a country where TB is common, or if you have been around someone who has TB. Your doctor will perform a skin test to see if you have an inactive TB infection. If necessary, your doctor will give you medication to treat this infection before you start using guselkumab injection. If you have any of the following symptoms of TB, or if you develop any of these symptoms during your treatment, call your doctor immediately: cough, chest pain, coughing up blood or mucus, weakness or tiredness, weight loss, loss of appetite, chills, fever, or night sweats.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Use the missed dose as soon as you remember it and then continue your regular dosing schedule. Do not use a double dose to make up for a missed one. Call your doctor if you are unclear about your dosing schedule.

What side effects can this medication cause?

Guselkumab injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • headache
  • redness, itching, swelling, pain, discoloration, or irritation at the injection site
  • joint pain
  • diarrhea

Some side effects can be serious. If you experience any of these symptoms or those listed in SPECIAL PRECAUTIONS, call your doctor immediately or get emergency medical treatment:

  • rash; hives; itching; feeling faint or lightheaded; swelling of the face, eyes, lips, mouth, throat, or tongue; trouble breathing; or chest or throat tightness

Guselkumab injection may cause other side effects. Call your doctor if you have any unusual problems while using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Store guselkumab injection in the refrigerator, but do not freeze. Keep the prefilled syringes or one press self injector devices in their original cartons to protect them from light.

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reachhttps://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies..

Brand names

  • Tremfya®
Last Revised - 03/15/2025