Guselkumab
Guselkumab is an immunosuppressant monoclonal antibody used to treat moderate to severe plaque psoriasis and psoriatic arthritis. It works by selectively binding to and blocking interleukin-23 (IL-23), a cytokine involved in inflammatory and immune responses, thereby reducing the abnormal immune activity that causes these conditions. This medication is administered by subcutaneous injection and is typically prescribed when other systemic therapies have not been adequate.
Guselkumab is a monoclonal antibody that treats psoriasis and psoriatic arthritis by blocking IL-23 to reduce inflammation.
Key facts at a glance
- ATC
- L04AC16
- RxNorm
- 1928588
- Generic
- Guselkumab
- Class
- atc-l04
- Brands
- Tremfya
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- prefilled syringe, injection
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
9 groupspregnancy
first trimesteravoid if possible
discontinue use at least 2 months before planned pregnancy; avoid use during pregnancy unless benefits significantly outweigh potential risks
standard prenatal monitoring; inform healthcare provider of exposure
Use with caution and monitor for adverse effects.
pregnancy
third trimesteravoid if possible
discontinue use in third trimester due to potential risk of neonatal immunogenicity; consider alternative therapies
standard prenatal monitoring; assess neonatal immune status after birth
Use with caution and monitor for adverse effects.
lactation
breastfeedingno specific adjustment
discontinue breastfeeding during treatment or discontinue therapy based on importance of drug to mother; consider pumping and discarding milk during treatment
monitor infant for infections and immune system development
Use with caution and monitor for adverse effects.
pediatric_age
under 18 yearsnot recommended
not approved for use in patients under 18 years; safety and efficacy not established
not applicable
geriatric
65 years and olderno dose adjustment required
use with caution; no overall differences in efficacy or safety observed in clinical trials but increased susceptibility to infections
regular monitoring for infections; assess overall immune function
Use with caution and monitor for adverse effects.
renal_impairment
mild to moderateno dose adjustment required
no dose adjustment needed; drug is a monoclonal antibody not renally excreted
standard clinical monitoring
renal_impairment
severeno specific adjustment recommended
use with caution; limited clinical data in severe renal impairment
standard clinical monitoring
Use with caution and monitor for adverse effects.
hepatic_impairment
mild to moderateno dose adjustment required
no dose adjustment needed; monoclonal antibodies metabolized by proteolysis not hepatic enzymes
standard clinical monitoring
hepatic_impairment
severeno specific adjustment recommended
limited clinical data in severe hepatic impairment; use with caution
monitor liver function tests
Use with caution and monitor for adverse effects.
Statistics and clinical data
FDA approval year
First FDA approval for plaque psoriasis
Drug class
Monoclonal antibody targeting interleukin-23
Common uses
Autoimmune inflammatory conditions
Route of administration
Method of drug delivery
Treats moderate to severe plaque psoriasis in adults who are candidates for systemic therapy or phototherapy, and active psoriatic arthritis (used alone or in combination with methotrexate).
Guselkumab is a human IgG1λ monoclonal antibody that selectively binds to the p19 subunit of interleukin-23 (IL-23), preventing it from interacting with the IL-23 receptor. This inhibits the IL-23-mediated inflammatory signaling that drives psoriatic disease.
Administered as a subcutaneous injection (typically 100 mg every 8 weeks after initial doses). As an immunosuppressant, it may increase risk of infections. Live vaccines should be avoided during treatment. Common side effects include upper respiratory infections, headache, and injection site reactions. Requires refrigeration and proper storage handling.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy