Living with chronic autoimmune conditions like psoriasis, Crohn’s disease, or ulcerative colitis can be physically and emotionally exhausting. Frequent flares, visible skin symptoms, and digestive discomfort often affect confidence and daily life. Ustekinumab (brand name Stelara) is a biologic medication that has helped transform care for many people by offering a targeted way to calm inflammation and restore quality of life.

What does Ustekinumab do?

Ustekinumab is used to treat several immune-mediated inflammatory diseases, including:

• Moderate to severe plaque psoriasis in adults and children aged 6 +.
• Active psoriatic arthritis in adults.
• Moderate to severe Crohn’s disease and ulcerative colitis in adults who haven’t responded well to other treatments.

By addressing the overactive immune system that drives these diseases, ustekinumab helps reduce inflammation, control symptoms, and improve daily comfort.

Patients with psoriasis often notice a significant reduction in skin plaques and itching, while those with Crohn’s disease or ulcerative colitis may experience fewer flare-ups, less abdominal pain, and improved bowel habits.

Clinical trials have shown ustekinumab’s strong and sustained effectiveness. For example, in psoriasis studies, many patients achieved clear or almost clear skin within 12 weeks of treatment (Papp et al., 2008). In Crohn’s and ulcerative colitis trials, ustekinumab significantly improved remission rates and endoscopic healing compared to placebo (Feagan et al., 2016).

How does Ustekinumab work?

Ustekinumab is a monoclonal antibody, a type of biologic therapy that precisely targets specific parts of the immune system. It works by blocking two proteins, interleukin-12 (IL-12) and interleukin-23 (IL-23), which play a central role in inflammation and immune cell activation.

By inhibiting IL-12 and IL-23, ustekinumab helps reduce the inflammatory signals that trigger immune cells to attack healthy tissues in the skin, joints, or intestines. This targeted approach helps control disease activity without broadly suppressing the entire immune system.

Clinically, this mechanism matters because it helps maintain long-term disease control while reducing flare frequency and the need for continuous steroids or stronger immunosuppressants.

Ustekinumab side effects

Most people tolerate ustekinumab well, but like all prescription medications, it can cause side effects. Most are mild and improve with time or supportive care.

Common side effects:

• Upper respiratory infections (such as sinus infections or sore throat)
• Headache
• Fatigue
• Injection site redness or itching

Less common or serious side effects:

• Increased risk of infections (including tuberculosis and shingles)
• Allergic reactions (rash, swelling, or breathing difficulty)
• Rare cases of cancer or reversible posterior leukoencephalopathy syndrome (a rare brain condition)

Because ustekinumab affects immune signaling, doctors screen patients for latent infections such as tuberculosis and hepatitis before starting treatment. Ongoing monitoring helps ensure early detection of any complications.

Patients should avoid live vaccines while taking ustekinumab and report symptoms like fever, persistent cough, or unusual skin changes promptly.

People with active infections, a history of certain cancers, or weakened immune systems should discuss risks carefully with their doctor before using this medication.

Ustekinumab dosage

Ustekinumab is given either as an injection under the skin (subcutaneous) or as an intravenous infusion, depending on the condition being treated.

• For psoriasis and psoriatic arthritis, treatment usually begins with a subcutaneous injection, followed by maintenance doses every few months.
• For Crohn’s disease and ulcerative colitis, patients typically start with an intravenous infusion, then switch to subcutaneous injections for ongoing maintenance.

This infrequent dosing schedule is one of ustekinumab’s major benefits, as it allows patients to maintain disease control without frequent injections or daily pills.

Doctors may monitor:

• Blood counts and liver function, to ensure treatment safety.
• Infection screening, before and during therapy.
• Response to treatment, using symptom tracking or imaging (like colonoscopy or skin assessment).

Older adults or those with chronic infections may require closer follow-up to ensure safety.

Does Ustekinumab have a generic version?

As of now, no generic or biosimilar version of ustekinumab is approved in the United States. It is marketed exclusively under the brand name Stelara by Janssen Biotech.

Because ustekinumab is a biologic (made from living cells rather than chemicals), any future alternatives will be biosimilars, not traditional generics. Biosimilars are required to demonstrate equivalent safety, purity, and effectiveness to the original product before FDA approval.

In some countries, biosimilar versions are under development, but they are not yet widely available for clinical use.

Conclusion

Ustekinumab represents a major advancement in the treatment of chronic autoimmune conditions such as psoriasis, psoriatic arthritis, Crohn’s disease, and ulcerative colitis. By precisely targeting key inflammatory proteins (IL-12 and IL-23), it helps restore balance to the immune system and reduce symptoms that affect skin, joints, and digestion.

While monitoring and infection precautions are essential, most patients find ustekinumab well-tolerated and life-changing in terms of comfort, mobility, and confidence.

As with any biologic therapy, ongoing communication with your healthcare provider is vital. When prescribed and monitored appropriately, ustekinumab is a safe and effective option that empowers patients to take control of their autoimmune condition and focus on living a fuller, healthier life.

References

1. U.S. Food and Drug Administration (FDA). (2019). Stelara (ustekinumab) prescribing information. https://www.fda.gov/
2. Mayo Clinic. (2023). Ustekinumab (injection route) description and precautions. https://medlineplus.gov/
3. Papp, K. A., et al. (2008). Ustekinumab, a human interleukin-12/23 monoclonal antibody, for moderate-to-severe psoriasis. New England Journal of Medicine, 358(6), 580–592. https://www.nejm.org/
4. Feagan, B. G., et al. (2016). Ustekinumab as induction and maintenance therapy for Crohn’s disease. New England Journal of Medicine, 375(20), 1946–1960. https://www.nejm.org/