Isotretinoin side effects: what 49,170 FDA adverse event reports show
Who reports
49,170 reports · 56% serious · 885 with death outcome · 64% female
Used for
Isotretinoin capsules are indicated for the treatment of severe recalcitrant nodular acne in non-pregnant patients 12 years of age and older with multiple inflammatory nodules with a diameter of 5 mm or greater. Because of significant adverse reactions.
What it is
Isotretinoin capsules, USP contain 10 mg, 20 mg, 25 mg, 30 mg, 35 mg or 40 mg of isotretinoin, USP (a retinoid) in hard gelatin capsules for oral administration. In addition to the active ingr.
Boxed warning
EMBRYO-FETAL TOXICITY – CONTRAINDICATED IN PREGNANCY Isotretinoin capsules can cause life-threatening birth defects and is contraindicated in pregnancy. There is an extremely high risk that life-threatening birth defects will result if pregnancy occurs while taking any amount of isotretinoin capsules even for short periods of time.
Causality screen of the 40 strongest signals
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- 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). 1,121 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Acne fulminans | 126 | 766.6 571.7–1,028.0ROR 768.6 · calibrated p 2e-15 ✓ | 261.2 EB05 225.1 · IC025 +6.7 3/3 methods agree vs other Retinoids: PRR 781.5 (248.7–2,455.6) | Labeled adverse reaction exact term | serious n=122 · ♀ 8% (drug 64%) · 93% clinician | not reported in cached trials |
| No adverse effect | 988 | 509.6 464.6–558.9ROR 520.0 · calibrated p 4e-14 ✓ | 229.7 EB05 217.9 · IC025 +7.6 3/3 methods agree vs other Retinoids: only this drug | Labeled (related wording) related wording | serious n=988 | not reported in cached trials |
| Inflammatory bowel disease | 5,252 | 494.6 475.7–514.2ROR 553.6 · calibrated p 2e-14 ✓ | 227.4 EB05 222.3 · IC025 +7.8 3/3 methods agree vs other Retinoids: PRR 880.4 (729.8–1,062.0) | Labeled — boxed warning exact term | serious PRR 239.2 · ♀ 42% (drug 64%) · 75% consumer | not reported in cached trials |
| Gastrointestinal injury | 1,261 | 374.1 347.0–403.4ROR 384.0 · calibrated p 9e-13 ✓ | 197.7 EB05 188.7 · IC025 +7.4 3/3 methods agree vs other Retinoids: PRR 7,821.1 (2,519.2–24,281.2) | Labeled (related wording) related wording | serious n=1,261 · ♀ 42% (drug 64%) | not reported in cached trials |
| Pregnancy test false positive | 185 | 303.4 251.2–366.5ROR 304.5 · calibrated p 1e-11 ✓ | 173.4 EB05 153.4 · IC025 +6.7 3/3 methods agree vs other Retinoids: only this drug | Lab value / disease marker | serious n=51 · ♀ 100% (drug 64%) | not reported in cached trials |
| Exposure via semen | 14 | 202.7 107.1–383.5ROR 202.7 · calibrated p 1e-8 ✓ | 115.8 EB05 73.3 · IC025 +3.7 3/3 methods agree vs other Retinoids: only this drug | Reporting / coding artifact | serious n=14 | not reported in cached trials |
| Proctitis ulcerative | 191 | 197.5 166.3–234.5ROR 198.3 · calibrated p 6e-10 ✓ | 132.9 EB05 117.8 · IC025 +6.4 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=190 | not reported in cached trials |
| Epiphyses premature fusion | 91 | 187.3 146.3–239.7ROR 187.6 · calibrated p 1e-9 ✓ | 126.4 EB05 106.1 · IC025 +5.9 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=88 · ♀ 22% (drug 64%) | not reported in cached trials |
| Nasal vestibulitis | 30 | 179.9 117.3–275.9ROR 180.0 · calibrated p 5e-9 ✓ | 117.0 EB05 85.9 · IC025 +4.8 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=30 · ♀ 34% (drug 64%) · 100% clinician | not reported in cached trials |
| Selective abortion | 52 | 177.5 128.4–245.4ROR 177.7 · calibrated p 3e-9 ✓ | 119.6 EB05 94.8 · IC025 +5.4 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=52 · ♀ 100% (drug 64%) · 94% clinician | not reported in cached trials |
| No adverse reaction | 42 | 169.5 118.5–242.6ROR 169.7 · calibrated p 5e-9 ✓ | 114.9 EB05 88.6 · IC025 +5.1 3/3 methods agree vs other Retinoids: only this drug | Likely indication confounding term in indications; also in warnings | serious n=42 · ♀ 87% (drug 64%) | not reported in cached trials |
| Xerosis | 340 | 164.4 145.1–186.4ROR 165.6 · calibrated p 2e-9 ✓ | 117.7 EB05 107.5 · IC025 +6.5 3/3 methods agree vs other Retinoids: PRR 395.4 (239.5–652.7) | Not in label — unassessed | serious n=182 | not reported in cached trials |
| Pregnancy test negative | 27 | 149.1 96.1–231.4ROR 149.2 · calibrated p 2e-8 ✓ | 102.5 EB05 74.0 · IC025 +4.6 3/3 methods agree vs other Retinoids: only this drug | Reporting / coding artifact | ♀ 100% (drug 64%) | not reported in cached trials |
| No adverse drug effect | 158 | 126.8 106.2–151.5ROR 127.2 · calibrated p 2e-8 ✓ | 96.5 EB05 84.5 · IC025 +6.0 3/3 methods agree vs other Retinoids: only this drug | Labeled (related wording) related wording | serious n=158 · 94% clinician | not reported in cached trials |
| Proctocolitis | 21 | 108.8 67.4–175.9ROR 108.9 · calibrated p 3e-7 ✓ | 80.5 EB05 55.6 · IC025 +4.1 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=21 | not reported in cached trials |
| Acne conglobata | 16 | 106.6 61.6–184.6ROR 106.7 · calibrated p 5e-7 ✓ | 77.6 EB05 50.7 · IC025 +3.7 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=10 | not reported in cached trials |
| Ileitis | 75 | 100.9 78.4–129.8ROR 101.1 · calibrated p 2e-7 ✓ | 79.9 EB05 65.9 · IC025 +5.4 3/3 methods agree vs other Retinoids: PRR 465.2 (146.7–1,474.9) | Labeled adverse reaction exact term | serious n=75 · ♀ 35% (drug 64%) | not reported in cached trials |
| Sapho syndrome | 43 | 96.0 69.0–133.7ROR 96.1 · calibrated p 3e-7 ✓ | 75.8 EB05 58.6 · IC025 +4.9 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=43 · ♀ 20% (drug 64%) · 100% clinician | not reported in cached trials |
| Unintended pregnancy | 1,919 | 95.8 91.3–100.6ROR 99.7 · calibrated p 1e-7 ✓ | 78.2 EB05 75.3 · IC025 +6.2 3/3 methods agree vs other Retinoids: PRR 11,902.2 (3,835.5–36,934.2) | Not in label — unassessed | serious PRR 91.3 · ♀ 100% (drug 64%) | not reported in cached trials |
| Lip dry | 1,581 | 91.4 86.6–96.4ROR 94.4 · calibrated p 2e-7 ✓ | 75.2 EB05 72.1 · IC025 +6.1 3/3 methods agree vs other Retinoids: PRR 134.3 (116.7–154.6) | Not in label — unassessed | serious n=1,013 | NCT00975143: 210/460 (45.7%) on Isotretinoin |
| Anotia | 15 | 87.5 50.1–152.5ROR 87.5 · calibrated p 2e-6 ✓ | 66.7 EB05 42.9 · IC025 +3.6 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=15 | not reported in cached trials |
| Crohn's disease | 1,140 | 83.7 78.6–89.1ROR 85.6 · calibrated p 4e-7 ✓ | 69.8 EB05 66.5 · IC025 +6.0 3/3 methods agree vs other Retinoids: PRR 623.9 (443.7–877.3) | Not in label — unassessed | serious n=1,137 · ♀ 41% (drug 64%) | not reported in cached trials |
| Abortion induced | 1,393 | 73.9 69.9–78.2ROR 76.1 · calibrated p 8e-7 ✓ | 63.0 EB05 60.2 · IC025 +5.9 3/3 methods agree vs other Retinoids: PRR 925.7 (636.9–1,345.4) | Labeled (related wording) related wording | serious PRR 62.7 · ♀ 100% (drug 64%) | not reported in cached trials |
| Ileal fistula | 13 | 69.1 38.4–124.2ROR 69.1 · calibrated p 9e-6 ✓ | 54.9 EB05 34.2 · IC025 +3.3 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=13 | not reported in cached trials |
| Transmission of drug via semen | 67 | 67.8 52.4–87.7ROR 67.9 · calibrated p 3e-6 ✓ | 57.6 EB05 46.9 · IC025 +5.0 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=66 · ♀ 27% (drug 64%) | not reported in cached trials |
| Drug exposure before pregnancy | 132 | 63.5 52.9–76.2ROR 63.6 · calibrated p 3e-6 ✓ | 54.9 EB05 47.4 · IC025 +5.2 3/3 methods agree vs other Retinoids: only this drug | Reporting / coding artifact | serious n=123 · ♀ 94% (drug 64%) | not reported in cached trials |
| Rectal polyp | 129 | 63.2 52.5–76.0ROR 63.4 · calibrated p 3e-6 ✓ | 54.6 EB05 47.2 · IC025 +5.2 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=129 · ♀ 42% (drug 64%) | not reported in cached trials |
| Purging | 13 | 61.3 34.3–109.7ROR 61.3 · calibrated p 2e-5 ✓ | 50.0 EB05 31.1 · IC025 +3.2 3/3 methods agree vs other Retinoids: PRR 80.6 (23.0–282.9) | Not in label — unassessed | – | not reported in cached trials |
| Intestinal haemorrhage | 707 | 61.0 56.4–66.0ROR 61.9 · calibrated p 3e-6 ✓ | 53.3 EB05 50.1 · IC025 +5.6 3/3 methods agree vs other Retinoids: PRR 657.8 (421.8–1,025.6) | Not in label — unassessed | serious n=706 · ♀ 36% (drug 64%) · 100% clinician | NCT00026312: 1/1,328 (0.1%) on Isotretinoin (serious AE) |
| Perirectal abscess | 137 | 59.6 49.8–71.3ROR 59.8 · calibrated p 5e-6 ✓ | 52.0 EB05 45.1 · IC025 +5.2 3/3 methods agree vs other Retinoids: PRR 849.7 (270.7–2,667.1) | Not in label — unassessed | serious n=137 · ♀ 31% (drug 64%) | not reported in cached trials |
| Chapped lips | 504 | 55.9 51.0–61.3ROR 56.5 · calibrated p 6e-6 ✓ | 49.4 EB05 45.9 · IC025 +5.4 3/3 methods agree vs other Retinoids: PRR 132.1 (103.1–169.3) | Labeled adverse reaction exact term | serious n=296 | NCT00975143: 32/460 (7.0%) on Isotretinoin |
| Anal polyp | 12 | 55.4 30.3–101.1ROR 55.4 · calibrated p 3e-5 ✓ | 45.7 EB05 27.9 · IC025 +3.1 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=12 | not reported in cached trials |
| Alopecia scarring | 19 | 54.3 33.7–87.5ROR 54.3 · calibrated p 2e-5 ✓ | 46.1 EB05 31.2 · IC025 +3.7 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=13 | not reported in cached trials |
| Personality change due to a general medical condition | 14 | 53.4 30.6–93.2ROR 53.4 · calibrated p 3e-5 ✓ | 44.8 EB05 28.4 · IC025 +3.3 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=14 | not reported in cached trials |
| Pregnancy test positive | 43 | 52.8 38.4–72.5ROR 52.8 · calibrated p 2e-5 ✓ | 46.1 EB05 35.7 · IC025 +4.4 3/3 methods agree vs other Retinoids: only this drug | Lab value / disease marker | serious n=26 · ♀ 100% (drug 64%) | not reported in cached trials |
| Pregnancy | 2,080 | 48.8 46.7–51.1ROR 50.9 · calibrated p 1e-5 ✓ | 43.8 EB05 42.3 · IC025 +5.4 3/3 methods agree vs other Retinoids: PRR 390.9 (319.7–478.1) | Labeled — boxed warning exact term | serious PRR 58.0 · ♀ 97% (drug 64%) | NCT00975143: 1/460 (0.2%) on Isotretinoin (serious AE) |
| Sacroiliitis | 188 | 46.9 40.3–54.5ROR 47.0 · calibrated p 2e-5 ✓ | 42.1 EB05 37.3 · IC025 +5.0 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=186 · 98% clinician | not reported in cached trials |
| Pouchitis | 82 | 44.8 35.7–56.2ROR 44.8 · calibrated p 3e-5 ✓ | 40.2 EB05 33.4 · IC025 +4.7 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=82 · ♀ 28% (drug 64%) | not reported in cached trials |
| Enterocolonic fistula | 12 | 44.6 24.6–80.8ROR 44.6 · calibrated p 1e-4 ✓ | 38.2 EB05 23.2 · IC025 +3.0 3/3 methods agree vs other Retinoids: only this drug | Not in label — unassessed | serious n=12 | not reported in cached trials |
| Irritable bowel syndrome | 2,014 | 44.3 42.4–46.4ROR 46.2 · calibrated p 2e-5 ✓ | 40.2 EB05 38.7 · IC025 +5.2 3/3 methods agree vs other Retinoids: PRR 177.6 (154.2–204.5) | Not in label — unassessed | serious PRR 51.9 | 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 Isotretinoin 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 (4 of 40 signal terms matched).
- NCT00026312 — Isotretinoin With or Without Dinutuximab, Aldesleukin, and Sargramostim Following Stem Cell Transplant in Trea (N=1449, PHASE3; 515 AE terms posted; arms: Regimen A; Regimen B)
- NCT00975143 — Efficacy and Safety of CIP-Isotretinoin in Patients With Severe Recalcitrant Nodular Acne (N=925, PHASE3; 26 AE terms posted; arms: CIP-Isotretinoin; Isotretinoin)
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 |
|---|---|---|---|---|---|---|
| Depression | 5,803 | 11.1 10.8–11.4ROR 12.4 · calibrated p 0.015 ✓ | 10.8 EB05 10.6 · IC025 +3.4 3/3 methods agree vs other Retinoids: PRR 261.4 (236.8–288.6) | Labeled — boxed warning exact term | serious PRR 13.2 | NCT00026312: 1/1,328 (0.1%) on Isotretinoin (serious AE) |
| Inflammatory bowel disease | 5,252 | 494.6 475.7–514.2ROR 553.6 · calibrated p 2e-14 ✓ | 227.4 EB05 222.3 · IC025 +7.8 3/3 methods agree vs other Retinoids: PRR 880.4 (729.8–1,062.0) | Labeled — boxed warning exact term | serious PRR 239.2 · ♀ 42% (drug 64%) · 75% consumer | not reported in cached trials |
| Colitis ulcerative | 3,808 | 39.8 38.5–41.1ROR 43.0 · calibrated p 3e-5 ✓ | 36.4 EB05 35.4 · IC025 +5.1 3/3 methods agree vs other Retinoids: PRR 723.0 (591.9–883.2) | Not in label — unassessed | serious PRR 40.2 · ♀ 42% (drug 64%) | not reported in cached trials |
| Dry skin | 2,425 | 8.0 7.7–8.3ROR 8.4 · calibrated p 0.058 | 7.9 EB05 7.6 · IC025 +2.9 3/3 methods agree vs other Retinoids: PRR 1.0 (0.9–1.0) | Labeled adverse reaction exact term | serious PRR 18.4 | NCT00026312: 4/1,328 (0.3%) on Isotretinoin (serious AE) |
| Suicidal ideation (thoughts of suicide) | 2,146 | 10.2 9.8–10.6ROR 10.6 · calibrated p 0.026 ✓ | 10.0 EB05 9.6 · IC025 +3.2 3/3 methods agree vs other Retinoids: PRR 330.0 (274.9–396.1) | Labeled — boxed warning synonym match | serious PRR 10.6 | NCT00026312: 1/1,328 (0.1%) on Isotretinoin (serious AE) |
| Pregnancy | 2,080 | 48.8 46.7–51.1ROR 50.9 · calibrated p 1e-5 ✓ | 43.8 EB05 42.3 · IC025 +5.4 3/3 methods agree vs other Retinoids: PRR 390.9 (319.7–478.1) | Labeled — boxed warning exact term | serious PRR 58.0 · ♀ 97% (drug 64%) | NCT00975143: 1/460 (0.2%) on Isotretinoin (serious AE) |
| Irritable bowel syndrome | 2,014 | 44.3 42.4–46.4ROR 46.2 · calibrated p 2e-5 ✓ | 40.2 EB05 38.7 · IC025 +5.2 3/3 methods agree vs other Retinoids: PRR 177.6 (154.2–204.5) | Not in label — unassessed | serious PRR 51.9 | not reported in cached trials |
| Headache | 1,992 | 1.4 1.3–1.4ROR 1.4 · calibrated p 0.557 | 1.4 EB05 1.3 · IC025 +0.4 vs other Retinoids: PRR 41.0 (38.0–44.4) | Labeled adverse reaction exact term | serious PRR 1.3 | NCT00026312: 11/1,328 (0.8%) on Isotretinoin (serious AE) |
| Arthralgia (joint pain) | 1,966 | 2.0 1.9–2.1ROR 2.1 · calibrated p 0.982 | 2.0 EB05 1.9 · IC025 +0.9 vs other Retinoids: PRR 57.8 (52.9–63.1) | Labeled — boxed warning exact term | serious PRR 1.7 | NCT00026312: 5/1,328 (0.4%) on Isotretinoin (serious AE) |
| Anxiety | 1,926 | 2.9 2.8–3.0ROR 3.0 · calibrated p 0.636 | 2.9 EB05 2.8 · IC025 +1.4 3/3 methods agree vs other Retinoids: PRR 58.7 (53.7–64.3) | Labeled adverse reaction exact term | serious PRR 3.6 | NCT00026312: 1/1,328 (0.1%) on Isotretinoin (serious AE) |
| Unintended pregnancy | 1,919 | 95.8 91.3–100.6ROR 99.7 · calibrated p 1e-7 ✓ | 78.2 EB05 75.3 · IC025 +6.2 3/3 methods agree vs other Retinoids: PRR 11,902.2 (3,835.5–36,934.2) | Not in label — unassessed | serious PRR 91.3 · ♀ 100% (drug 64%) | not reported in cached trials |
| Product dose omission issue | 1,763 | 2.7 2.5–2.8ROR 2.7 · calibrated p 0.728 | 2.6 EB05 2.5 · IC025 +1.3 3/3 methods agree vs other Retinoids: PRR 162.4 (140.5–187.7) | Reporting / coding artifact | serious PRR 0.6 · ♀ 86% (drug 64%) · 77% consumer | not reported in cached trials |
| Exposure during pregnancy | 1,710 | 12.0 11.5–12.6ROR 12.4 · calibrated p 0.015 ✓ | 11.7 EB05 11.3 · IC025 +3.5 3/3 methods agree vs other Retinoids: PRR 74.5 (67.1–82.8) | Reporting / coding artifact | serious PRR 17.4 · ♀ 100% (drug 64%) | not reported in cached trials |
| Lip dry | 1,581 | 91.4 86.6–96.4ROR 94.4 · calibrated p 2e-7 ✓ | 75.2 EB05 72.1 · IC025 +6.1 3/3 methods agree vs other Retinoids: PRR 134.3 (116.7–154.6) | Not in label — unassessed | serious n=1,013 | NCT00975143: 210/460 (45.7%) on Isotretinoin |
| Adverse drug reaction | 1,558 | 7.5 7.2–7.9ROR 7.8 · calibrated p 0.073 | 7.4 EB05 7.1 · IC025 +2.8 3/3 methods agree vs other Retinoids: PRR 247.8 (205.4–298.9) | Reporting / coding artifact | serious PRR 0.7 | 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.
- Proctitis ulcerative — n=191, PRR 197.5
- Epiphyses premature fusion — n=91, PRR 187.3
- Nasal vestibulitis — n=30, PRR 179.9
- Selective abortion — n=52, PRR 177.5
- Xerosis — n=340, PRR 164.4
- Proctocolitis — n=21, PRR 108.8
- Sapho syndrome — n=43, PRR 96.0
- Unintended pregnancy — n=1,919, PRR 95.8
- Lip dry — n=1,581, PRR 91.4 (also seen in trial arm)
- Crohn's disease — n=1,140, PRR 83.7
✓ A hand-written Bradford Hill causality assessment exists for this drug: Isotretinoin (Accutane) ↔ Depression / suicidal ideation.
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 Isotretinoin?
In FDA FAERS, the most frequently co-reported reaction terms for Isotretinoin are depression, inflammatory bowel disease, colitis ulcerative, dry skin, suicidal ideation, pregnancy. 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 Isotretinoin have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: EMBRYO-FETAL TOXICITY – CONTRAINDICATED IN PREGNANCY Isotretinoin capsules can cause life-threatening birth defects and is contraindicated in pregnancy. There is an extremely high risk that life-threatening birth defects will result if pregnancy occurs while taking any amount of isotretinoin capsules even for short periods of time.
Do FAERS signals prove that Isotretinoin 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 1cf11710-f966-4529-8e08-02175f588bca, effective 20260820; matched on
openfda.generic_name.exact:"ISOTRETINOIN") - 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, 1,161 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
ISOTRETINOIN, 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.