Comprehensive Clinical Guide to Risankizumab (Skyrizi): Dosing, Contraindications, and Safety

　　1.Indications

　　Risankizumab(brand name Skyrizi)is an interleukin-23(IL-23)inhibitor indicated for the treatment of moderate-to-severe plaque psoriasis in adults eligible for systemic therapy or phototherapy,active psoriatic arthritis,and moderate-to-severe active Crohn's disease.

　　2.Dosage and Administration

　　Dosage varies by condition.For plaque psoriasis and psoriatic arthritis,the dose is 150 mg via subcutaneous injection at weeks 0 and 4,then every 12 weeks.Rotate injection sites among the abdomen,thigh,or upper arm.

　　For Crohn's disease,induction involves 600 mg intravenous infusions at weeks 0,4,and 8.Maintenance is 360 mg subcutaneously every 8 weeks.

　　Allow the medication to reach room temperature for 30 minutes before use;do not shake.If a dose is missed,administer it as soon as possible and adjust the schedule accordingly.

　　3.Contraindications and Infection Risk

　　Contraindications include hypersensitivity to the drug,active tuberculosis(TB),severe active infections(e.g.,sepsis,pneumonia),and active hepatitis B(HBsAg or HBV DNA positive).TB screening(T-SPOT or PPD)is mandatory before starting;prophylactic treatment for latent TB is required for at least 4 weeks prior to initiation.Patients should seek immediate medical attention for fever or cough during treatment.

　　4.Safety and Adverse Reactions

　　Common adverse reactions(≥5%)include upper respiratory infection(12%),headache(7%),fatigue(6%),and injection site reactions(erythema,pain,~4%).Serious infections occur in about 1%of patients;anaphylactic shock is rare.No significant increase in hepatotoxicity or cytopenia has been observed.

　　5.Drug Interactions and Vaccinations

　　Risankizumab does not interact with drugs metabolized by CYP450 enzymes,allowing co-administration with methotrexate,cyclosporine,or corticosteroids without dose adjustment.Avoid live vaccines(e.g.,MMR,varicella);inactivated vaccines(e.g.,influenza,pneumococcal,COVID-19)are permissible.

　　6.Special Populations and Storage

　　No dose adjustment is needed for the elderly(≥65 years),though infection risk may be higher.No renal or hepatic dose adjustment is deemed necessary based on metabolic pathways,but caution is advised.Use during pregnancy only if benefits outweigh risks;exercise caution during breastfeeding.

　　Store prefilled syringes refrigerated at 2–8°C;do not freeze.Protect from light.Once removed from refrigeration and kept at≤25°C,use within 14 days.Dispose of expired medication via healthcare facilities.