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Tremfya Side Effects

Generic name: guselkumab

Medically reviewed by Philip Thornton, DipPharm. Last updated on Aug 5, 2022.

Note: This document contains side effect information about guselkumab. Some of the dosage forms listed on this page may not apply to the brand name Tremfya.

For the Consumer

Applies to guselkumab: subcutaneous solution

Side effects requiring immediate medical attention

Along with its needed effects, guselkumab (the active ingredient contained in Tremfya) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking guselkumab:

More common

Less Common

  • Burning or stinging of the skin
  • diarrhea
  • itching in the genital or other skin areas
  • loss of appetite
  • nausea
  • painful cold sores or blisters on the lips, nose, eyes, or genitals
  • scaling
  • stomach pain


  • Headache, severe and throbbing
  • hives or welts, itching, skin rash
  • white patches in the mouth or throat or on the tongue

Side effects not requiring immediate medical attention

Some side effects of guselkumab may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

  • Bleeding, blistering, burning, coldness, discoloration of the skin, feeling of pressure, hives, infection, inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness, stinging, swelling, tenderness, tingling, ulceration, or warmth at the injection site
  • difficulty in moving
  • muscle pain or stiffness
  • pain in the joints


  • Redness of the skin

For Healthcare Professionals

Applies to guselkumab: subcutaneous solution


Very common (10% or more): Infections (23%)

Common (1% to 10%): Tinea infections, herpes simplex infections, immunogenicity[Ref]


Common (1% to 10%): Injection site reactions (e.g., injection site erythema, bruising, hematoma, hemorrhage, swelling, edema, pruritus, pain, discoloration, induration, inflammation, urticaria)[Ref]


Common (1% to 10%): Arthralgia[Ref]


Common (1% to 10%): Elevated liver enzymes[Ref]


Very common (10% or more): Respiratory tract infection (e.g., nasopharyngitis, upper respiratory tract infection, pharyngitis, viral upper respiratory tract infection) (14%)[Ref]

Nervous system

Common (1% to 10%): Headache[Ref]


Common (1% to 10%): Diarrhea, gastroenteritis (including viral gastroenteritis)[Ref]


Uncommon (0.1% to 1%): Hypersensitivity

Frequency not reported: Anaphylaxis[Ref]


Common (1% to 10%): Urticaria, rash[Ref]

Frequently asked questions


1. "Product Information. Tremfya (guselkumab)." Janssen Biotech, Inc. (2017):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.