Drug · FAERS side-effect profile with label screen
Onabotulinumtoxina side effects: what 76,722 FDA adverse event reports show
Drug class
Acetylcholine Release Inhibitor, Neuromuscular Blocker
FDA label (Established Pharmacologic Class) · compare the class
Brand names
Botox
openFDA label
Who reports
76,722 reports · 19% serious · 2,108 with death outcome · 87% female
openFDA FAERS counts, all years, deduplication not applied
Used for
BOTOX is an acetylcholine release inhibitor and a neuromuscular blocking agent indicated for: Treatment of overactive bladder (OAB) with symptoms of urge urinary incontinence, urgency, and frequency, in adults who have an inadequate response to or are .
FDA label, Indications and Usage
What it is
OnabotulinumtoxinA is a sterile, vacuum-dried purified botulinum toxin type A, produced from fermentation of Hall strain Clostridium botulinum type A, and intended for intramuscular, intradetrusor and intradermal use.
FDA label, Description section
Boxed warning
DISTANT SPREAD OF TOXIN EFFECT Postmarketing reports indicate that the effects of BOTOX and all botulinum toxin products may spread from the area of injection to produce symptoms consistent with botulinum toxin effects.
FDA label
How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation.
Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)?
That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.
Causality screen of the 40 strongest signals
Labeled adverse reaction 5Labeled (related wording) 5Likely indication confounding 5Reporting / coding artifact 6Lab value / disease marker 1Not in label — unassessed 18
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only (and, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,139 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Mephisto sign | 49 | 731.4 426.2–1,255.3ROR 731.9 · calibrated p 5e-14 ✓ | 183.2 EB05 144.1 · IC025 +5.6 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 34.2 (16.8–69.5) | Labeled adverse reaction exact term | – | not reported in cached trials |
| Brow ptosis | 448 | 590.0 500.1–696.2ROR 593.5 · calibrated p 1e-14 ✓ | 183.9 EB05 170.0 · IC025 +7.1 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 25.6 (20.8–31.5) | Not in label — unassessed | serious n=24 | not reported in cached trials |
| Botulism | 385 | 334.8 288.3–388.8ROR 336.4 · calibrated p 4e-12 ✓ | 148.5 EB05 136.5 · IC025 +6.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 14.4 (12.0–17.2) | Not in label — unassessed | serious n=374 | not reported in cached trials |
| Multiple use of single-use product | 2,857 | 292.0 277.1–307.7ROR 303.2 · calibrated p 9e-12 ✓ | 140.3 EB05 136.0 · IC025 +7.0 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 2,561.3 (1,220.1–5,376.9) | Labeled (related wording) related wording | serious n=20 | not reported in cached trials |
| Eyelid sensory disorder | 73 | 164.8 123.2–220.6ROR 165.0 · calibrated p 4e-9 ✓ | 99.9 EB05 82.1 · IC025 +5.5 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Not in label — unassessed | – | not reported in cached trials |
| Face lift | 20 | 131.1 76.8–223.7ROR 131.1 · calibrated p 1e-7 ✓ | 81.7 EB05 55.9 · IC025 +4.1 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Not in label — unassessed | – | not reported in cached trials |
| Eyelid ptosis | 3,129 | 121.7 116.7–126.9ROR 126.8 · calibrated p 2e-8 ✓ | 84.0 EB05 81.6 · IC025 +6.3 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 28.7 (26.4–31.1) | Labeled adverse reaction exact term | serious n=373 | not reported in cached trials |
| Product administered from unauthorised provider | 23 | 99.7 61.8–160.8ROR 99.7 · calibrated p 5e-7 ✓ | 69.0 EB05 48.4 · IC025 +4.2 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 18.0 (8.1–40.3) | Reporting / coding artifact | serious n=16 | not reported in cached trials |
| Facial paresis | 936 | 97.7 90.7–105.2ROR 98.9 · calibrated p 1e-7 ✓ | 71.8 EB05 68.0 · IC025 +6.0 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 69.1 (55.4–86.2) | Labeled adverse reaction exact term | serious n=123 | not reported in cached trials |
| Facial asymmetry | 243 | 93.8 81.1–108.5ROR 94.1 · calibrated p 2e-7 ✓ | 69.4 EB05 62.4 · IC025 +5.7 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 23.1 (17.6–30.3) | Not in label — unassessed | serious n=37 | not reported in cached trials |
| Postnatal growth restriction | 28 | 87.5 57.1–134.0ROR 87.5 · calibrated p 9e-7 ✓ | 63.5 EB05 46.1 · IC025 +4.3 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Not in label — unassessed | serious n=28 · ♀ 0% (drug 87%) · 100% clinician | not reported in cached trials |
| Lagophthalmos | 83 | 69.3 54.4–88.1ROR 69.3 · calibrated p 2e-6 ✓ | 54.6 EB05 45.4 · IC025 +5.0 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 47.4 (25.3–88.8) | Labeled adverse reaction exact term | serious n=21 | not reported in cached trials |
| Cervicogenic headache | 24 | 59.7 38.4–92.9ROR 59.7 · calibrated p 1e-5 ✓ | 47.3 EB05 33.5 · IC025 +3.9 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Likely indication confounding shares a disease stem with the indications wording | serious n=22 | not reported in cached trials |
| Residual urine volume increased | 21 | 58.8 36.7–94.2ROR 58.8 · calibrated p 1e-5 ✓ | 46.5 EB05 32.1 · IC025 +3.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Lab value / disease marker | – | not reported in cached trials |
| Product preparation error | 3,647 | 58.4 56.3–60.4ROR 61.2 · calibrated p 4e-6 ✓ | 48.1 EB05 46.8 · IC025 +5.5 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 29.4 (27.3–31.7) | Reporting / coding artifact | serious n=36 | not reported in cached trials |
| Pineal gland cyst | 19 | 42.5 26.2–69.0ROR 42.6 · calibrated p 9e-5 ✓ | 35.7 EB05 24.1 · IC025 +3.5 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Not in label — unassessed | serious n=19 | not reported in cached trials |
| Product preparation issue | 731 | 39.1 36.2–42.3ROR 39.5 · calibrated p 6e-5 ✓ | 34.2 EB05 32.2 · IC025 +4.9 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 34.0 (28.3–40.8) | Reporting / coding artifact | serious n=13 | not reported in cached trials |
| Skin wrinkling | 329 | 37.6 33.6–42.2ROR 37.8 · calibrated p 8e-5 ✓ | 33.1 EB05 30.2 · IC025 +4.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 93.8 (61.0–144.5) | Not in label — unassessed | serious n=29 | not reported in cached trials |
| Autonomic dysreflexia | 17 | 32.2 19.5–53.2ROR 32.2 · calibrated p 4e-4 ✓ | 28.0 EB05 18.5 · IC025 +3.2 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Labeled adverse reaction exact term | serious n=15 | not reported in cached trials |
| Neuromuscular toxicity | 34 | 29.7 20.8–42.3ROR 29.7 · calibrated p 4e-4 ✓ | 26.5 EB05 19.8 · IC025 +3.7 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 1.3 (0.9–1.9) | Likely indication confounding shares a disease stem with the indications wording | serious n=20 | not reported in cached trials |
| Skin indentation | 43 | 27.5 20.1–37.6ROR 27.5 · calibrated p 6e-4 ✓ | 24.8 EB05 19.2 · IC025 +3.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 22.5 (11.9–42.6) | Not in label — unassessed | – | not reported in cached trials |
| Lid sulcus deepened | 34 | 27.4 19.3–39.0ROR 27.4 · calibrated p 6e-4 ✓ | 24.7 EB05 18.5 · IC025 +3.6 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 42.7 (16.7–109.1) | Not in label — unassessed | – | not reported in cached trials |
| Facial discomfort | 56 | 25.1 19.1–33.0ROR 25.1 · calibrated p 8e-4 ✓ | 22.9 EB05 18.3 · IC025 +3.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 11.7 (7.5–18.2) | Not in label — unassessed | – | not reported in cached trials |
| Cutis laxa | 21 | 22.8 14.6–35.7ROR 22.8 · calibrated p 0.002 ✓ | 20.7 EB05 14.2 · IC025 +3.1 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Not in label — unassessed | – | not reported in cached trials |
| Therapeutic response decreased | 4,511 | 22.0 21.4–22.7ROR 23.3 · calibrated p 9e-4 ✓ | 20.4 EB05 19.9 · IC025 +4.3 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 31.9 (29.7–34.3) | Reporting / coding artifact | serious PRR 2.8 | not reported in cached trials |
| Migraine without aura | 22 | 21.7 14.0–33.4ROR 21.7 · calibrated p 0.002 ✓ | 19.8 EB05 13.6 · IC025 +3.1 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Likely indication confounding shares a disease stem with the indications wording | serious n=20 | not reported in cached trials |
| Facial spasm | 77 | 20.1 15.9–25.3ROR 20.1 · calibrated p 0.002 ✓ | 18.7 EB05 15.4 · IC025 +3.7 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 53.7 (26.9–107.1) | Likely indication confounding term in indications; also in warnings | serious n=30 | not reported in cached trials |
| Muscle hypertrophy | 23 | 18.8 12.3–28.7ROR 18.8 · calibrated p 0.004 ✓ | 17.3 EB05 11.9 · IC025 +3.0 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 20.6 (8.8–48.0) | Likely indication confounding shares a disease stem with the indications wording | – | not reported in cached trials |
| Incorrect product formulation administered | 54 | 18.7 14.2–24.6ROR 18.7 · calibrated p 0.003 ✓ | 17.4 EB05 13.8 · IC025 +3.5 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Reporting / coding artifact | 100% consumer | not reported in cached trials |
| Skin tightness | 298 | 18.5 16.4–20.8ROR 18.6 · calibrated p 0.003 ✓ | 17.3 EB05 15.8 · IC025 +3.9 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 62.3 (42.8–90.7) | Not in label — unassessed | serious n=22 | not reported in cached trials |
| Poor quality product administered | 514 | 14.4 13.2–15.8ROR 14.5 · calibrated p 0.008 ✓ | 13.7 EB05 12.8 · IC025 +3.6 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 537.6 (240.4–1,202.1) | Not in label — unassessed | – | not reported in cached trials |
| Occipital neuralgia | 28 | 14.3 9.8–20.9ROR 14.3 · calibrated p 0.011 ✓ | 13.2 EB05 9.3 · IC025 +2.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 25.1 (11.0–57.5) | Not in label — unassessed | serious n=15 · 100% consumer | not reported in cached trials |
| Post-traumatic neck syndrome | 40 | 14.1 10.3–19.4ROR 14.1 · calibrated p 0.011 ✓ | 13.2 EB05 9.9 · IC025 +3.0 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 5.7 (3.7–8.8) | Not in label — unassessed | serious n=37 | not reported in cached trials |
| Skin laxity | 20 | 14.0 8.9–21.9ROR 14.0 · calibrated p 0.013 ✓ | 12.6 EB05 8.1 · IC025 +2.6 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 31.4 (10.7–91.8) | Not in label — unassessed | – | not reported in cached trials |
| Injection site oedema | 82 | 13.8 11.0–17.2ROR 13.8 · calibrated p 0.011 ✓ | 13.0 EB05 10.8 · IC025 +3.2 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 46.8 (24.9–87.8) | Labeled (related wording) related wording | serious n=16 | not reported in cached trials |
| Hypoaesthesia eye | 28 | 13.7 9.4–20.0ROR 13.7 · calibrated p 0.013 ✓ | 12.6 EB05 8.8 · IC025 +2.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 43.9 (15.4–125.2) | Labeled (related wording) related wording | – | not reported in cached trials |
| Extraocular muscle paresis | 22 | 13.5 8.8–20.8ROR 13.5 · calibrated p 0.014 ✓ | 12.3 EB05 8.1 · IC025 +2.6 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 34.5 (11.9–100.2) | Labeled (related wording) related wording | – | not reported in cached trials |
| Dropped head syndrome | 18 | 13.2 8.2–21.2ROR 13.2 · calibrated p 0.017 ✓ | 11.7 EB05 7.3 · IC025 +2.5 3/3 methods agree vs other Acetylcholine Release Inhibitors: only this drug | Not in label — unassessed | serious n=11 | not reported in cached trials |
| Wrong technique in drug usage process | 1,587 | 12.3 11.7–12.9ROR 12.5 · calibrated p 0.014 ✓ | 11.8 EB05 11.3 · IC025 +3.5 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 177.8 (136.3–232.1) | Reporting / coding artifact | serious PRR 4.7 | not reported in cached trials |
| Eyelid function disorder | 33 | 11.8 8.3–16.7ROR 11.8 · calibrated p 0.021 ✓ | 10.8 EB05 7.8 · IC025 +2.7 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 25.9 (12.0–56.0) | Labeled (related wording) related wording | serious n=14 | not reported in cached trials |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Onabotulinumtoxina as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (0 of 40 signal terms matched).
- NCT00535938 — MDs on Botox Utility (MOBILITY) (N=1372, phase n/a; 53 AE terms posted; arms: Naïve to Botox® Treatment; Non-naïve to Botox® Treatment)
Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Drug ineffective (drug did not work) | 26,602 | 5.6 5.6–5.7ROR 8.1 · calibrated p 0.065 | 5.5 EB05 5.5 · IC025 +2.4 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 23.6 (23.0–24.1) | Reporting / coding artifact | serious PRR 2.2 | not reported in cached trials |
| Off label use (used outside approved label) | 11,542 | 3.7 3.6–3.7ROR 4.1 · calibrated p 0.352 | 3.6 EB05 3.6 · IC025 +1.8 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 9.9 (9.7–10.2) | Reporting / coding artifact | serious PRR 2.9 | not reported in cached trials |
| Therapeutic response decreased | 4,511 | 22.0 21.4–22.7ROR 23.3 · calibrated p 9e-4 ✓ | 20.4 EB05 19.9 · IC025 +4.3 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 31.9 (29.7–34.3) | Reporting / coding artifact | serious PRR 2.8 | not reported in cached trials |
| Headache | 4,082 | 1.8 1.7–1.8ROR 1.8 · calibrated p 0.848 | 1.8 EB05 1.7 · IC025 +0.8 vs other Acetylcholine Release Inhibitors: PRR 16.1 (15.2–17.0) | Likely indication confounding term in indications; also in warnings | serious PRR 3.4 | NCT00535938: 1/866 (0.1%) on Onabotulinumtoxina (serious AE) |
| Product preparation error | 3,647 | 58.4 56.3–60.4ROR 61.2 · calibrated p 4e-6 ✓ | 48.1 EB05 46.8 · IC025 +5.5 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 29.4 (27.3–31.7) | Reporting / coding artifact | serious n=36 | not reported in cached trials |
| Injection site pain (pain where injected) | 3,438 | 3.1 3.0–3.2ROR 3.2 · calibrated p 0.559 | 3.1 EB05 3.0 · IC025 +1.6 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 25.6 (23.8–27.6) | Labeled adverse reaction exact term | serious PRR 4.7 | NCT00535938: 1/866 (0.1%) on Onabotulinumtoxina (serious AE) |
| Eyelid ptosis | 3,129 | 121.7 116.7–126.9ROR 126.8 · calibrated p 2e-8 ✓ | 84.0 EB05 81.6 · IC025 +6.3 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 28.7 (26.4–31.1) | Labeled adverse reaction exact term | serious n=373 | not reported in cached trials |
| Multiple use of single-use product | 2,857 | 292.0 277.1–307.7ROR 303.2 · calibrated p 9e-12 ✓ | 140.3 EB05 136.0 · IC025 +7.0 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 2,561.3 (1,220.1–5,376.9) | Labeled (related wording) related wording | serious n=20 | not reported in cached trials |
| Migraine | 2,351 | 6.9 6.6–7.2ROR 7.1 · calibrated p 0.094 | 6.8 EB05 6.5 · IC025 +2.7 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 12.0 (11.2–12.9) | Likely indication confounding term in indications; also in warnings | serious PRR 17.0 | not reported in cached trials |
| Nausea | 2,178 | 0.8 0.7–0.8ROR 0.7 · calibrated p 0.154 | 0.8 EB05 0.7 · IC025 -0.5 PRR-only: not supported by EBGM or IC vs other Acetylcholine Release Inhibitors: PRR 10.8 (10.1–11.6) | Labeled adverse reaction exact term | serious PRR 2.2 | not reported in cached trials |
| Pain | 1,893 | 0.8 0.8–0.9ROR 0.8 · calibrated p 0.205 | 0.8 EB05 0.8 · IC025 -0.3 PRR-only: not supported by EBGM or IC vs other Acetylcholine Release Inhibitors: PRR 10.4 (9.7–11.2) | Likely indication confounding term in indications; also in warnings | serious PRR 1.8 | NCT00535938: 1/866 (0.1%) on Onabotulinumtoxina (serious AE) |
| Fatigue (tiredness) | 1,841 | 0.6 0.6–0.7ROR 0.6 · calibrated p 0.101 | 0.6 EB05 0.6 · IC025 -0.7 PRR-only: not supported by EBGM or IC vs other Acetylcholine Release Inhibitors: PRR 10.9 (10.1–11.7) | Labeled — boxed warning synonym match | serious PRR 1.8 | not reported in cached trials |
| Muscular weakness | 1,804 | 4.4 4.2–4.6ROR 4.5 · calibrated p 0.300 | 4.3 EB05 4.2 · IC025 +2.0 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 10.4 (9.7–11.2) | Labeled adverse reaction exact term | serious PRR 9.7 | NCT00535938: 1/866 (0.1%) on Onabotulinumtoxina (serious AE) |
| Dizziness | 1,793 | 1.0 0.9–1.0ROR 1.0 · calibrated p 0.296 | 1.0 EB05 0.9 · IC025 -0.1 PRR-only: not supported by EBGM or IC vs other Acetylcholine Release Inhibitors: PRR 10.0 (9.3–10.8) | Labeled adverse reaction exact term | serious PRR 2.3 | not reported in cached trials |
| Wrong technique in product usage process | 1,718 | 2.3 2.2–2.4ROR 2.4 · calibrated p 0.872 | 2.3 EB05 2.2 · IC025 +1.1 3/3 methods agree vs other Acetylcholine Release Inhibitors: PRR 55.6 (47.9–64.4) | Reporting / coding artifact | serious PRR 2.1 | not reported in cached trials |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Brow ptosis — n=448, PRR 590.0
- Botulism — n=385, PRR 334.8
- Eyelid sensory disorder — n=73, PRR 164.8
- Face lift — n=20, PRR 131.1
- Facial asymmetry — n=243, PRR 93.8
- Postnatal growth restriction — n=28, PRR 87.5
- Skin wrinkling — n=329, PRR 37.6
- Skin indentation — n=43, PRR 27.5
- Lid sulcus deepened — n=34, PRR 27.4
- Facial discomfort — n=56, PRR 25.1
✓ A hand-written Bradford Hill causality assessment exists for this drug: Onabotulinumtoxina ↔ Product Preparation Error.
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Onabotulinumtoxina?
In FDA FAERS, the most frequently co-reported reaction terms for Onabotulinumtoxina are headache, injection site pain, eyelid ptosis, multiple use of single-use product, migraine, nausea. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Onabotulinumtoxina have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: DISTANT SPREAD OF TOXIN EFFECT Postmarketing reports indicate that the effects of BOTOX and all botulinum toxin products may spread from the area of injection to produce symptoms consistent with botulinum toxin effects.
Do FAERS signals prove that Onabotulinumtoxina causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 33d066a9-34ff-4a1a-b38b-d10983df3300, effective 20231118; matched on
openfda.generic_name.exact:"ONABOTULINUMTOXINA") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 1,179 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath - ClinicalTrials.gov API v2 (query
ONABOTULINUMTOXINA, results-bearing studies sorted by enrollment)
Page generated 2026-10-14. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.