Drug · FAERS side-effect profile with label screen
Sulfamethoxazole and Trimethoprim side effects: what 83,846 FDA adverse event reports show
Drug class
Sulfonamide Antimicrobial, Dihydrofolate Reductase Inhibitor Antibacterial
FDA label (Established Pharmacologic Class)
Who reports
83,846 reports · 83% serious · 10,343 with death outcome · 50% female
openFDA FAERS counts, all years, deduplication not applied
Used for
To reduce the development of drug-resistant bacteria and maintain the effectiveness of sulfamethoxazole and trimethoprim tablets and other antibacterial drugs, sulfamethoxazole and trimethoprim tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria.
FDA label, Indications and Usage
What it is
Sulfamethoxazole is an isoxazole (1,2-oxazole) compound having a methyl substituent at the 5-position and a 4-aminobenzenesulfonamido group at the 3-position.
PubChem CID 5329 (ChEBI)
Boxed warning
None in the current 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 2Labeled (related wording) 1Likely indication confounding 1Lab value / disease marker 11Not in label — unassessed 25
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.
- 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). 1,212 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 |
|---|---|---|---|---|---|---|
| Vaginal flatulence | 167 | 303.9 242.3–381.3ROR 304.6 · calibrated p 1e-11 ✓ | 134.4 EB05 118.1 · IC025 +6.3 3/3 methods agree | Not in label — unassessed | serious n=167 · ♀ 100% (drug 50%) | no trial arm names this drug |
| Pulmonary vasculitis | 102 | 59.7 48.1–74.1ROR 59.7 · calibrated p 5e-6 ✓ | 47.8 EB05 40.5 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious n=102 · ♀ 0% (drug 50%) | no trial arm names this drug |
| C-reactive protein | 166 | 55.9 47.2–66.1ROR 56.0 · calibrated p 8e-6 ✓ | 45.5 EB05 40.0 · IC025 +5.1 3/3 methods agree | Lab value / disease marker | serious n=166 · ♀ 100% (drug 50%) · 100% clinician | no trial arm names this drug |
| Subcutaneous drug absorption impaired | 96 | 53.4 42.8–66.5ROR 53.4 · calibrated p 1e-5 ✓ | 43.7 EB05 36.8 · IC025 +4.8 3/3 methods agree | Not in label — unassessed | serious n=95 · ♀ 100% (drug 50%) · 100% clinician | no trial arm names this drug |
| Sleep disorder due to general medical condition, insomnia type | 1,017 | 46.8 43.8–50.0ROR 47.4 · calibrated p 2e-5 ✓ | 39.5 EB05 37.5 · IC025 +5.2 3/3 methods agree | Labeled (related wording) related wording | serious n=1,017 · ♀ 100% (drug 50%) · 94% clinician | no trial arm names this drug |
| Deep vein thrombosis postoperative | 305 | 45.9 40.7–51.9ROR 46.1 · calibrated p 2e-5 ✓ | 38.8 EB05 35.3 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious n=305 · ♀ 100% (drug 50%) · 93% clinician | no trial arm names this drug |
| Muscle injury | 1,202 | 42.8 40.3–45.5ROR 43.4 · calibrated p 3e-5 ✓ | 36.6 EB05 34.9 · IC025 +5.1 3/3 methods agree | Not in label — unassessed | serious PRR 27.5 · ♀ 100% (drug 50%) · 94% clinician | no trial arm names this drug |
| X-ray abnormal | 251 | 40.8 35.7–46.6ROR 40.9 · calibrated p 5e-5 ✓ | 35.1 EB05 31.6 · IC025 +4.8 3/3 methods agree | Lab value / disease marker | serious n=251 · ♀ 100% (drug 50%) · 93% clinician | no trial arm names this drug |
| Duodenal ulcer perforation | 1,015 | 40.0 37.5–42.8ROR 40.5 · calibrated p 5e-5 ✓ | 34.5 EB05 32.8 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious PRR 23.9 · ♀ 100% (drug 50%) · 95% clinician | no trial arm names this drug |
| Adjustment disorder with depressed mood | 271 | 38.7 34.1–44.0ROR 38.9 · calibrated p 7e-5 ✓ | 33.5 EB05 30.3 · IC025 +4.8 3/3 methods agree | Not in label — unassessed | serious n=270 · ♀ 100% (drug 50%) · 100% clinician | no trial arm names this drug |
| Folliculitis | 1,384 | 38.6 36.5–40.8ROR 39.2 · calibrated p 6e-5 ✓ | 33.5 EB05 32.0 · IC025 +5.0 3/3 methods agree | Not in label — unassessed | serious PRR 27.2 · ♀ 97% (drug 50%) · 94% clinician | no trial arm names this drug |
| Anti-cyclic citrullinated peptide antibody | 88 | 37.9 30.3–47.4ROR 37.9 · calibrated p 9e-5 ✓ | 32.7 EB05 27.4 · IC025 +4.4 3/3 methods agree | Lab value / disease marker | serious n=88 · ♀ 100% (drug 50%) · 100% clinician | no trial arm names this drug |
| Antineutrophil cytoplasmic antibody positive | 96 | 37.9 30.5–46.9ROR 37.9 · calibrated p 9e-5 ✓ | 32.7 EB05 27.6 · IC025 +4.5 3/3 methods agree | Lab value / disease marker | serious n=96 · ♀ 0% (drug 50%) | no trial arm names this drug |
| Swollen joint count increased | 399 | 36.6 32.9–40.6ROR 36.8 · calibrated p 9e-5 ✓ | 31.9 EB05 29.4 · IC025 +4.8 3/3 methods agree | Lab value / disease marker | serious n=399 · ♀ 100% (drug 50%) · 100% clinician | no trial arm names this drug |
| Anti-cyclic citrullinated peptide antibody positive | 873 | 34.9 32.5–37.5ROR 35.3 · calibrated p 1e-4 ✓ | 30.7 EB05 29.0 · IC025 +4.8 3/3 methods agree | Lab value / disease marker | serious PRR 21.4 · ♀ 100% (drug 50%) · 95% clinician | no trial arm names this drug |
| Mite allergy | 77 | 34.2 27.0–43.4ROR 34.2 · calibrated p 2e-4 ✓ | 30.0 EB05 24.7 · IC025 +4.3 3/3 methods agree | Not in label — unassessed | serious n=76 · ♀ 0% (drug 50%) | no trial arm names this drug |
| Spirometry abnormal | 70 | 33.7 26.3–43.3ROR 33.8 · calibrated p 2e-4 ✓ | 29.6 EB05 24.2 · IC025 +4.2 3/3 methods agree | Lab value / disease marker | serious n=70 · ♀ 0% (drug 50%) | no trial arm names this drug |
| Febrile bone marrow aplasia | 493 | 33.3 30.3–36.6ROR 33.5 · calibrated p 1e-4 ✓ | 29.4 EB05 27.3 · IC025 +4.7 3/3 methods agree | Not in label — unassessed | serious n=493 · 100% clinician | no trial arm names this drug |
| Facet joint syndrome | 362 | 32.3 29.0–36.1ROR 32.5 · calibrated p 2e-4 ✓ | 28.7 EB05 26.3 · IC025 +4.6 3/3 methods agree | Not in label — unassessed | serious n=362 · ♀ 100% (drug 50%) · 93% clinician | no trial arm names this drug |
| Dislocation of vertebra | 250 | 31.6 27.7–36.0ROR 31.7 · calibrated p 2e-4 ✓ | 28.0 EB05 25.2 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=250 · ♀ 100% (drug 50%) · 93% clinician | no trial arm names this drug |
| Rheumatic fever | 489 | 31.4 28.6–34.5ROR 31.6 · calibrated p 2e-4 ✓ | 28.0 EB05 25.9 · IC025 +4.6 3/3 methods agree | Labeled adverse reaction exact term | serious n=489 · ♀ 100% (drug 50%) · 95% clinician | no trial arm names this drug |
| Female genital tract fistula | 189 | 30.8 26.4–35.8ROR 30.8 · calibrated p 2e-4 ✓ | 27.4 EB05 24.3 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=188 · ♀ 100% (drug 50%) | no trial arm names this drug |
| Lupus vulgaris | 122 | 28.5 23.6–34.3ROR 28.5 · calibrated p 4e-4 ✓ | 25.5 EB05 21.9 · IC025 +4.2 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious n=122 · ♀ 100% (drug 50%) · 100% clinician | no trial arm names this drug |
| Mycotic allergy | 86 | 28.3 22.7–35.4ROR 28.4 · calibrated p 4e-4 ✓ | 25.4 EB05 21.2 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=82 · ♀ 0% (drug 50%) | no trial arm names this drug |
| Helicobacter infection | 1,023 | 27.8 26.1–29.7ROR 28.1 · calibrated p 4e-4 ✓ | 25.1 EB05 23.8 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious PRR 18.4 · ♀ 100% (drug 50%) · 95% clinician | no trial arm names this drug |
| Immune reconstitution syndrome | 129 | 27.3 22.7–32.7ROR 27.3 · calibrated p 5e-4 ✓ | 24.6 EB05 21.2 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious n=127 · ♀ 0% (drug 50%) · 100% clinician | no trial arm names this drug |
| Hypofibrinogenaemia | 93 | 26.4 21.4–32.8ROR 26.5 · calibrated p 6e-4 ✓ | 23.9 EB05 20.1 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious n=92 · ♀ 0% (drug 50%) · 100% clinician | no trial arm names this drug |
| Rheumatoid factor positive | 494 | 23.3 21.3–25.6ROR 23.5 · calibrated p 9e-4 ✓ | 21.4 EB05 19.8 · IC025 +4.2 3/3 methods agree | Lab value / disease marker | serious n=494 · ♀ 100% (drug 50%) · 97% clinician | no trial arm names this drug |
| Hand deformity | 1,056 | 21.9 20.6–23.3ROR 22.1 · calibrated p 0.001 ✓ | 20.2 EB05 19.2 · IC025 +4.2 3/3 methods agree | Not in label — unassessed | serious PRR 15.2 · ♀ 100% (drug 50%) · 96% clinician | no trial arm names this drug |
| Aplasia | 156 | 21.1 17.9–24.9ROR 21.2 · calibrated p 0.002 ✓ | 19.5 EB05 17.0 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=156 · 100% clinician | no trial arm names this drug |
| Blood pressure diastolic abnormal | 196 | 20.6 17.8–23.8ROR 20.6 · calibrated p 0.002 ✓ | 19.0 EB05 16.9 · IC025 +4.0 3/3 methods agree | Lab value / disease marker | serious n=190 · 100% clinician | no trial arm names this drug |
| Pemphigus | 946 | 20.5 19.2–21.9ROR 20.7 · calibrated p 0.002 ✓ | 19.0 EB05 18.0 · IC025 +4.1 3/3 methods agree | Not in label — unassessed | serious PRR 13.2 · ♀ 100% (drug 50%) · 95% clinician | no trial arm names this drug |
| Radiculopathy | 200 | 20.4 17.7–23.6ROR 20.5 · calibrated p 0.002 ✓ | 18.9 EB05 16.8 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious n=199 · ♀ 100% (drug 50%) | no trial arm names this drug |
| Dust allergy | 68 | 18.9 14.8–24.2ROR 18.9 · calibrated p 0.003 ✓ | 17.5 EB05 14.3 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=67 · ♀ 0% (drug 50%) | no trial arm names this drug |
| Neuritis | 106 | 18.4 15.1–22.5ROR 18.5 · calibrated p 0.003 ✓ | 17.2 EB05 14.6 · IC025 +3.7 3/3 methods agree | Labeled adverse reaction exact term | serious n=106 · ♀ 0% (drug 50%) | no trial arm names this drug |
| C-reactive protein abnormal | 435 | 18.1 16.5–20.0ROR 18.2 · calibrated p 0.003 ✓ | 17.0 EB05 15.7 · IC025 +3.9 3/3 methods agree | Lab value / disease marker | serious n=435 · ♀ 100% (drug 50%) · 95% clinician | no trial arm names this drug |
| Proctitis | 190 | 18.1 15.6–21.0ROR 18.1 · calibrated p 0.003 ✓ | 16.9 EB05 15.0 · IC025 +3.8 3/3 methods agree | Not in label — unassessed | serious n=190 · ♀ 100% (drug 50%) | no trial arm names this drug |
| Retinitis | 106 | 16.9 13.9–20.6ROR 16.9 · calibrated p 0.005 ✓ | 15.8 EB05 13.4 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=106 · ♀ 100% (drug 50%) · 100% clinician | no trial arm names this drug |
| Irritable bowel syndrome | 1,325 | 16.5 15.6–17.4ROR 16.7 · calibrated p 0.004 ✓ | 15.5 EB05 14.8 · IC025 +3.9 3/3 methods agree | Not in label — unassessed | serious PRR 13.5 · ♀ 100% (drug 50%) · 93% clinician | no trial arm names this drug |
| Blood pressure systolic abnormal | 154 | 16.4 14.0–19.3ROR 16.5 · calibrated p 0.005 ✓ | 15.4 EB05 13.5 · IC025 +3.6 3/3 methods agree | Lab value / disease marker | serious n=149 | no trial arm names this drug |
Clinical concept groups
MedDRA splits one clinical problem across several terms (e.g. "neutropenia", "neutrophil count decreased", "agranulocytosis"), which dilutes term-level signals. These rows count reports with any term in a concept group (an exact union, not a sum), compared with all other drugs. Groups are hand-built and listed in the methods.
| Concept | Reports | PRR 95% CI | Reading |
|---|---|---|---|
| Severe cutaneous reaction | 2,275 | 7.97.5–8.2 | signal |
| Neutropenia / agranulocytosis | 5,792 | 6.05.8–6.1 | signal |
| Interstitial lung disease | 1,643 | 4.34.1–4.6 | signal |
| Thrombocytopenia | 3,640 | 4.24.1–4.3 | signal |
| Kidney injury | 6,804 | 3.83.7–3.9 | signal |
| Liver injury | 4,413 | 3.73.6–3.8 | signal |
| Anaemia | 4,058 | 3.43.3–3.5 | signal |
| Hyponatraemia | 1,083 | 3.43.2–3.6 | signal |
| Opportunistic infection | 1,807 | 3.33.2–3.5 | signal |
| Serious infection | 9,517 | 3.13.0–3.2 | signal |
| Pancreatitis | 908 | 2.82.7–3.0 | signal |
| Venous thromboembolism | 1,867 | 2.22.1–2.3 | signal |
| Rhabdomyolysis / myopathy | 625 | 1.91.8–2.1 | raised |
| Arrhythmia / qt | 1,328 | 1.71.6–1.8 | raised |
| Gi bleeding | 1,178 | 1.61.5–1.7 | raised |
| Heart failure | 1,062 | 1.51.4–1.6 | raised |
Trial evidence (ClinicalTrials.gov)
ClinicalTrials.gov returned results-bearing trials mentioning Sulfamethoxazole and Trimethoprim only as a background or rescue medication (NCT00729937, NCT00080119); no trial listing it as the tested intervention was cached, so no trial cross-check is shown.
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 |
|---|---|---|---|---|---|---|
| Pyrexia (fever) | 6,296 | 4.6 4.5–4.7ROR 4.9 · calibrated p 0.245 | 4.5 EB05 4.5 · IC025 +2.1 3/3 methods agree | Labeled (related wording) related wording | age-adj. PRR 3.7 · serious PRR 3.8 | no trial arm names this drug |
| Off label use (used outside approved label) | 5,719 | 1.7 1.6–1.7ROR 1.7 · calibrated p 0.769 | 1.6 EB05 1.6 · IC025 +0.7 | Reporting / coding artifact | age-adj. PRR 1.5 · serious PRR 1.8 | no trial arm names this drug |
| Fatigue (tiredness) | 5,409 | 1.7 1.7–1.8ROR 1.8 · calibrated p 0.828 | 1.7 EB05 1.7 · IC025 +0.8 | Labeled adverse reaction exact term | age-adj. PRR 1.4 · serious PRR 1.8 | no trial arm names this drug |
| Diarrhoea (diarrhea) | 4,950 | 1.9 1.9–2.0ROR 2.0 · calibrated p 0.938 | 1.9 EB05 1.9 · IC025 +0.9 | Likely indication confounding term in indications; also in warnings | age-adj. PRR 1.6 · serious PRR 1.9 | no trial arm names this drug |
| Nausea | 4,886 | 1.6 1.5–1.6ROR 1.6 · calibrated p 0.697 | 1.5 EB05 1.5 · IC025 +0.6 | Labeled adverse reaction exact term | age-adj. PRR 1.3 · serious PRR 1.6 | no trial arm names this drug |
| Rash | 4,491 | 2.6 2.5–2.7ROR 2.7 · calibrated p 0.733 | 2.6 EB05 2.5 · IC025 +1.3 3/3 methods agree | Labeled adverse reaction exact term | age-adj. PRR 2.4 · serious PRR 3.2 | no trial arm names this drug |
| Dyspnoea (shortness of breath) | 4,479 | 2.0 1.9–2.0ROR 2.0 · calibrated p 0.968 | 2.0 EB05 1.9 · IC025 +0.9 | Labeled adverse reaction exact term | age-adj. PRR 1.7 · serious PRR 1.8 | no trial arm names this drug |
| Pain | 4,114 | 1.7 1.6–1.7ROR 1.7 · calibrated p 0.776 | 1.7 EB05 1.6 · IC025 +0.7 | Labeled adverse reaction exact term | age-adj. PRR 1.7 · serious PRR 1.7 · ♀ 72% (drug 50%) | no trial arm names this drug |
| Drug ineffective (drug did not work) | 3,805 | 0.7 0.7–0.7ROR 0.7 · calibrated p 0.135 | 0.7 EB05 0.7 · IC025 -0.5 PRR-only: not supported by EBGM or IC | Reporting / coding artifact | age-adj. PRR 0.8 · serious PRR 1.2 · ♀ 72% (drug 50%) | no trial arm names this drug |
| Vomiting | 3,792 | 2.0 2.0–2.1ROR 2.1 · calibrated p 0.987 | 2.0 EB05 2.0 · IC025 +1.0 | Labeled adverse reaction exact term | age-adj. PRR 1.7 · serious PRR 1.9 | no trial arm names this drug |
| Pneumonia (lung infection) | 3,473 | 2.7 2.6–2.8ROR 2.8 · calibrated p 0.703 | 2.7 EB05 2.6 · IC025 +1.4 3/3 methods agree | Likely indication confounding term in indications; also in warnings | age-adj. PRR 2.3 · serious PRR 1.9 | no trial arm names this drug |
| Headache | 3,358 | 1.3 1.3–1.4ROR 1.4 · calibrated p 0.546 | 1.3 EB05 1.3 · IC025 +0.4 | Labeled adverse reaction exact term | age-adj. PRR 1.2 · serious PRR 1.6 · ♀ 73% (drug 50%) | no trial arm names this drug |
| Drug hypersensitivity | 3,337 | 4.4 4.2–4.5ROR 4.5 · calibrated p 0.297 | 4.3 EB05 4.2 · IC025 +2.0 3/3 methods agree | Labeled (related wording) related wording | age-adj. PRR 3.8 · serious PRR 3.9 · ♀ 82% (drug 50%) | no trial arm names this drug |
| Pruritus (itching) | 3,050 | 2.0 2.0–2.1ROR 2.1 · calibrated p 0.979 | 2.0 EB05 2.0 · IC025 +1.0 | Labeled adverse reaction exact term | age-adj. PRR 1.7 · serious PRR 2.9 · ♀ 77% (drug 50%) | no trial arm names this drug |
| Asthenia (weakness) | 2,957 | 2.0 1.9–2.0ROR 2.0 · calibrated p 0.949 | 2.0 EB05 1.9 · IC025 +0.9 | Not in label — unassessed | age-adj. PRR 1.6 · serious PRR 1.7 | no trial arm names this drug |
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.
- Vaginal flatulence — n=167, PRR 303.9
- Pulmonary vasculitis — n=102, PRR 59.7
- Subcutaneous drug absorption impaired — n=96, PRR 53.4
- Deep vein thrombosis postoperative — n=305, PRR 45.9
- Muscle injury — n=1,202, PRR 42.8
- Duodenal ulcer perforation — n=1,015, PRR 40.0
- Adjustment disorder with depressed mood — n=271, PRR 38.7
- Folliculitis — n=1,384, PRR 38.6
- Mite allergy — n=77, PRR 34.2
- Febrile bone marrow aplasia — n=493, PRR 33.3
✓ A hand-written Bradford Hill causality assessment exists for this drug: Trimethoprim (and co-trimoxazole) ↔ Hyperkalaemia.
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 Sulfamethoxazole and Trimethoprim?
In FDA FAERS, the most frequently co-reported reaction terms for Sulfamethoxazole and Trimethoprim are pyrexia, fatigue, diarrhoea, nausea, rash, dyspnoea. 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 Sulfamethoxazole and Trimethoprim have an FDA boxed warning?
No. The FDA label retrieved for Sulfamethoxazole and Trimethoprim has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Sulfamethoxazole and Trimethoprim 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 08500fcb-dbec-4ac2-91c3-189d27907ec0, effective 20260717; matched on
openfda.generic_name.exact:"SULFAMETHOXAZOLE AND TRIMETHOPRIM") - PubChem CID 5329 description (ChEBI)
- 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, 1,252 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
SULFAMETHOXAZOLE, 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.