What the label lists and what reports show
Bimekizumab side effects
Bimekizumab's FDA label: “Most common adverse reactions are: Psoriasis and Hidradenitis Suppurativa (incidence ≥ 1%): upper respiratory tract infections, oral candidiasis, headache, injection site reactions, tinea infections, gastroenteritis, Herpes simplex infections, acne …” FAERS holds 21,176 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is psoriatic arthropathy (1,622 reports).
- No generic listed
Check it at the source: the bimekizumab FDA label on DailyMed (effective June 16, 2025); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of BIMZELX?BIMZELX may cause serious side effects, including: See " What is important information I should know about BIMZELX? " Elevated liver enzyme levels. Your healthcare provider will do blood tests to check your liver enzyme levels before starting treatment and during treatment with BIMZELX. Your healthcare provider may temporarily stop or permanently stop your treatment with BIMZELX if you develop liver problems. Call your healthcare provider right away if you develop any signs or symptoms of liver problems, including: pain on the right side of your stomach-area feeling very tired loss of appetite nausea and vomiting itching dark urine light-colored stool yellowing of your skin or the whites of your eyes Inflammatory bowel disease. New cases of inflammatory bowel disease or "flare-ups" have happened with BIMZELX. […]
Source: FDA drug label, UCB, Inc., effective June 16, 2025 (SPL set 26b88358-871f-4c80-9d80-b2fb16477f81), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common adverse reactions are: Psoriasis and Hidradenitis Suppurativa (incidence ≥ 1%): upper respiratory tract infections, oral candidiasis, headache, injection site reactions, tinea infections, gastroenteritis, Herpes simplex infections, acne, folliculitis, other candida infections, and fatigue.
Table 1: Adverse Reactions Occurring in ≥1% of Subjects with Plaque Psoriasis in the BIMZELX Group and More Frequently than in the Placebo Group in Trials Ps-1 and Ps-2
| Reaction | BIMZELX N=670 n (%) | Placebo N=169 n (%) |
|---|---|---|
| URI Upper Respiratory Infections include nasopharyngitis, upper respiratory tract… | 102 (15) | 24 (14) |
| Oral Candidiasis Oral Candidiasis includes oral candidiasis, oropharyngeal candidiasis,… | 61 (9) | 0 (0) |
| Headache | 22 (3) | 0 (0) |
| Injection Site Reactions Injection Site Reactions include injection site reaction,… | 19 (3) | 2 (1) |
| Tinea Infections Tinea Infections include tinea pedis, fungal skin infection, tinea… | 18 (3) | 1 (1) |
| Gastroenteritis Gastroenteritis includes Enterovirus infection, gastroenteritis,… | 12 (2) | 0 (0) |
| Herpes Simplex Infections Herpes Simplex Infections include herpes simplex and oral herpes | 9 (1) | 0 (0) |
| Acne | 8 (1) | 0 (0) |
| Folliculitis | 8 (1) | 0 (0) |
| Other Candida Infections Other Candida Infections include vulvovaginal candidiasis,… | 7 (1) | 1 (1) |
| Fatigue | 7 (1) | 0 (0) |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following adverse reactions have been observed with BIMZELX and are discussed in greater detail in other sections of the labeling: Suicidal Ideation and Behavior [see Warnings and Precautions (5.1) ] Infections [see Warnings and Precautions (5.2) ] Liver Biochemical Abnormalities [see Warnings and Precautions (5.4) ] Inflammatory Bowel Disease [see Warnings and Precautions (5.5) ] Most common adverse reactions are: Psoriasis and Hidradenitis Suppurativa (incidence ≥ 1%): upper respiratory tract infections, oral candidiasis, headache, injection site reactions, tinea infections, gastroenteritis, Herpes simplex infections, acne, folliculitis, other candida infections, and fatigue. ( 6.1 ) Psoriatic Arthritis (incidence ≥ 2%): upper respiratory tract infections, oral candidiasis, headache, diarrhea, and urinary tract infection. ( 6.1 ) Non-Radiographic Axial Spondyloarthritis (incidence ≥ 2%): upper respiratory tract infections, oral candidiasis, headache, diarrhea, cough, fatigue, musculoskeletal pain, myalgia, tonsilitis, transaminase increase, and urinary tract infection. ( 6.1 ) Ankylosing Spondylitis (incidence ≥ 2%): upper respiratory tract infections, oral candidiasis, headache, diarrhea, injection site pain, rash and vulvovaginal mycotic infection.
Source: FDA drug label, UCB, Inc., effective June 16, 2025 (SPL set 26b88358-871f-4c80-9d80-b2fb16477f81), via openFDA; the full label on DailyMed
What do FAERS reports show?
21,176 reports list bimekizumab among the medicines taken, each a report of something that happened, not proof the medicine caused it; 147 are coded as a death and 1,909 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Reports rose sharply in 2025 (10,927, against a median of 3 a year): FAERS counts follow reporting, which news, litigation and label changes can drive, not how often a reaction happens. Of the 15 reactions below, 8 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Bimekizumab: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions