Skyrizi (Risankizumab) Side Effects: What to Expect and When to Call Your Doctor

Skyrizi (risankizumab-rzaa) is generally well-tolerated compared to older biologics. Clinical trials across tens of thousands of patients have shown a favorable safety profile, with no boxed (black box) warnings on the label. But like any biologic medication that affects the immune system, Skyrizi does carry risks that patients and caregivers should know about.

This guide covers the most common and most serious side effects of Skyrizi, organized by what to watch for and when to seek help.

Most Common Side Effects of Skyrizi

The following side effects occur in at least 1% of patients treated for plaque psoriasis or psoriatic arthritis:

Upper respiratory infections — such as the common cold, nasopharyngitis, or sinusitis. This is the most frequently reported side effect. Skyrizi lowers immune system activity, making infections more likely.

Headache — reported in a meaningful percentage of patients in clinical trials; usually mild to moderate.

Fatigue — feeling tired or low-energy, particularly early in treatment.

Injection site reactions — redness, bruising, itching, pain, or swelling at the injection site. Usually mild and temporary.

Tinea (fungal) infections — such as ringworm, athlete's foot (tinea pedis), or jock itch (tinea cruris). More common with Skyrizi than some other biologics.

Side Effects for Crohn's Disease and Ulcerative Colitis Patients

For patients treated for Crohn's disease or ulcerative colitis, additional side effects reported during maintenance therapy (occurring in more than 3% of patients) include:

Joint pain (arthralgia)

Abdominal pain

Low red blood cell count (anemia) — symptoms include fatigue, dizziness, or shortness of breath

Fever (pyrexia)

Back pain

Urinary tract infections

Serious Side Effects: Know the Warning Signs

While rare, the following serious side effects can occur with Skyrizi. Seek immediate medical attention if you experience any of these.

Severe Allergic Reactions (Anaphylaxis)

Stop using Skyrizi and get emergency medical help immediately if you experience any of the following signs of a serious allergic reaction:

Fainting, dizziness, or feeling lightheaded (low blood pressure)

Swelling of your face, eyelids, lips, mouth, tongue, or throat

Trouble breathing or throat tightness

Hives or skin rash accompanied by breathing difficulty

Serious Infections (Including TB)

Skyrizi lowers your immune system's ability to fight infections. Serious infections that have been reported include pneumonia, sepsis, and cellulitis. Most importantly, Skyrizi can reactivate latent tuberculosis (TB). Your doctor will screen you for TB before starting Skyrizi and may treat you for latent TB before beginning therapy.

Call your doctor right away if you develop fever, chills, persistent cough, night sweats, or unexplained weight loss while on Skyrizi.

Liver Problems (Crohn's Disease / UC Patients Only)

Patients receiving Skyrizi IV infusions for Crohn's disease or UC may experience liver enzyme changes. A case of drug-induced liver injury with rash leading to hospitalization was reported in clinical trials. Your doctor will monitor your liver function with blood tests before starting therapy and during the first 12+ weeks of IV induction.

Tell your doctor immediately if you notice unexplained rash, nausea, vomiting, abdominal pain, fatigue, yellowing of the skin or eyes (jaundice), or dark urine.

Live Vaccines: What to Know

You should not receive live vaccines while on Skyrizi. Live vaccines include MMR (measles, mumps, rubella), varicella (chickenpox), yellow fever, and certain influenza vaccines. Complete all recommended vaccinations before starting Skyrizi. If you are pregnant while on Skyrizi, delay live-virus immunizations for any exposed infant for at least 5 months after birth.

What Skyrizi Does NOT Cause (Compared to Some Other Biologics)

Skyrizi's label does not include warnings for inflammatory bowel disease worsening (unlike IL-17 inhibitors like Cosentyx and Taltz), depression or suicidal ideation (unlike brodalumab), or routine liver monitoring requirements during psoriasis/PsA treatment. No boxed warning exists for Skyrizi as of 2026.

See also: Skyrizi Drug Interactions: What to Avoid. Once you're managing side effects and need to find a pharmacy, medfinder can help locate a specialty pharmacy near you.