Drug · FAERS side-effect profile with label screen
Acetaminophen and Codeine side effects: what 12,111 FDA adverse event reports show
Drug class
Not stated in label
Label matched
Acetaminophen (Acetaminophen)
closest FDA label found for this product string; brand list suppressed because the label is a related product, not an exact match
Who reports
12,111 reports · 92% serious · 3,267 with death outcome · 68% female
openFDA FAERS counts, all years, deduplication not applied
Used for
temporarily relieves minor aches and pains due to: headache muscular aches backache minor pain of arthritis the common cold toothache premenstrual and menstrual cramps temporarily reduces fever
FDA label, Indications and Usage
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
Lab value / disease marker 8Not in label — unassessed 32
What the badges mean
- 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 flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 1,026 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 |
|---|---|---|---|---|---|---|
| Thiopurine methyltransferase decreased | 11 | 816.6 398.2–1,674.8ROR 817.3 · χ² 5,522 / p <1e-300 | 282.0 EB05 168.0 · IC025 +3.4 3/3 methods agree | Lab value / disease marker | serious n=11 | no trial arm names this drug |
| Hepatic enzyme | 40 | 696.9 482.7–1,006.2ROR 699.2 · χ² 19,248 / p <1e-300 | 400.1 EB05 306.5 · IC025 +5.6 3/3 methods agree | Not in label — unassessed | serious n=40 · ♀ 100% (drug 68%) · 100% clinician | no trial arm names this drug |
| Subcutaneous drug absorption impaired | 144 | 624.0 516.0–754.6ROR 631.5 · χ² 65,145 / p <1e-300 | 431.0 EB05 375.1 · IC025 +7.2 3/3 methods agree | Not in label — unassessed | serious n=144 · ♀ 100% (drug 68%) · 97% clinician | no trial arm names this drug |
| Facet joint syndrome | 779 | 570.1 526.8–617.1ROR 609.2 · χ² 331,408 / p <1e-300 | 423.2 EB05 398.8 · IC025 +8.3 3/3 methods agree | Not in label — unassessed | serious n=779 · ♀ 100% (drug 68%) · 96% clinician | no trial arm names this drug |
| Vaginal flatulence | 67 | 486.8 371.3–638.2ROR 489.5 · χ² 24,899 / p <1e-300 | 342.0 EB05 278.6 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=67 · ♀ 100% (drug 68%) | no trial arm names this drug |
| Duodenal ulcer perforation | 1,491 | 442.4 419.1–467.0ROR 504.3 · χ² 521,312 / p <1e-300 | 350.0 EB05 335.3 · IC025 +8.2 3/3 methods agree | Not in label — unassessed | serious PRR 219.0 · ♀ 100% (drug 68%) · 93% clinician | no trial arm names this drug |
| Computerised tomogram thorax | 12 | 426.9 226.8–803.4ROR 427.3 · χ² 3,745 / p <1e-300 | 221.6 EB05 135.1 · IC025 +3.6 3/3 methods agree | Not in label — unassessed | serious n=12 | no trial arm names this drug |
| Swollen joint count | 48 | 420.3 306.6–576.1ROR 422.0 · χ² 15,777 / p <1e-300 | 297.5 EB05 233.3 · IC025 +5.8 3/3 methods agree | Not in label — unassessed | serious n=48 · ♀ 100% (drug 68%) · 94% clinician | no trial arm names this drug |
| Deep vein thrombosis postoperative | 382 | 419.7 375.8–468.8ROR 433.4 · χ² 127,760 / p <1e-300 | 331.5 EB05 304.5 · IC025 +7.7 3/3 methods agree | Not in label — unassessed | serious n=382 · ♀ 100% (drug 68%) | no trial arm names this drug |
| Adjustment disorder with depressed mood | 391 | 417.5 374.4–465.7ROR 431.4 · χ² 130,224 / p <1e-300 | 330.2 EB05 303.7 · IC025 +7.7 3/3 methods agree | Not in label — unassessed | serious n=391 · ♀ 100% (drug 68%) · 95% clinician | no trial arm names this drug |
| X-ray abnormal | 342 | 411.2 365.9–462.1ROR 423.1 · χ² 112,471 / p <1e-300 | 325.6 EB05 297.6 · IC025 +7.6 3/3 methods agree | Lab value / disease marker | serious n=342 · ♀ 100% (drug 68%) · 95% clinician | no trial arm names this drug |
| C-reactive protein | 172 | 405.6 343.8–478.5ROR 411.5 · χ² 55,774 / p <1e-300 | 316.4 EB05 278.7 · IC025 +7.1 3/3 methods agree | Lab value / disease marker | serious n=172 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Rheumatic fever | 822 | 402.2 373.5–433.0ROR 431.4 · χ² 265,956 / p <1e-300 | 323.2 EB05 305.1 · IC025 +8.0 3/3 methods agree | Not in label — unassessed | serious n=822 · ♀ 100% (drug 68%) · 95% clinician | no trial arm names this drug |
| Anti-cyclic citrullinated peptide antibody positive | 1,334 | 400.9 378.8–424.4ROR 450.4 · χ² 430,807 / p <1e-300 | 323.4 EB05 309.1 · IC025 +8.1 3/3 methods agree | Lab value / disease marker | serious PRR 203.4 · ♀ 100% (drug 68%) · 93% clinician | no trial arm names this drug |
| Lupus vulgaris | 214 | 380.2 328.2–440.5ROR 387.0 · χ² 65,892 / p <1e-300 | 302.7 EB05 270.2 · IC025 +7.3 3/3 methods agree | Not in label — unassessed | serious n=214 · ♀ 100% (drug 68%) · 91% clinician | no trial arm names this drug |
| Swollen joint count increased | 549 | 370.5 338.4–405.6ROR 388.1 · χ² 165,961 / p <1e-300 | 301.4 EB05 280.8 · IC025 +7.8 3/3 methods agree | Lab value / disease marker | serious n=549 · ♀ 100% (drug 68%) · 95% clinician | no trial arm names this drug |
| Dislocation of vertebra | 384 | 361.8 324.6–403.4ROR 373.7 · χ² 113,732 / p <1e-300 | 294.4 EB05 270.5 · IC025 +7.6 3/3 methods agree | Not in label — unassessed | serious n=384 · ♀ 100% (drug 68%) · 93% clinician | no trial arm names this drug |
| Peripheral venous disease | 682 | 357.2 329.5–387.2ROR 378.5 · χ² 200,082 / p <1e-300 | 293.1 EB05 275.1 · IC025 +7.8 3/3 methods agree | Not in label — unassessed | serious n=682 · ♀ 100% (drug 68%) · 95% clinician | no trial arm names this drug |
| Grip strength | 39 | 350.5 248.4–494.4ROR 351.6 · χ² 10,988 / p <1e-300 | 254.7 EB05 194.4 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious n=39 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Anti-cyclic citrullinated peptide antibody | 109 | 338.4 275.7–415.3ROR 341.4 · χ² 30,321 / p <1e-300 | 269.2 EB05 229.4 · IC025 +6.6 3/3 methods agree | Lab value / disease marker | serious n=109 · ♀ 100% (drug 68%) · 94% clinician | no trial arm names this drug |
| Muscle injury | 1,333 | 336.3 318.0–355.6ROR 377.8 · χ² 372,156 / p <1e-300 | 280.0 EB05 267.6 · IC025 +7.9 3/3 methods agree | Not in label — unassessed | serious PRR 190.0 · ♀ 100% (drug 68%) · 93% clinician | no trial arm names this drug |
| Hypocholesterolaemia | 48 | 320.1 235.3–435.5ROR 321.4 · χ² 12,593 / p <1e-300 | 243.6 EB05 191.1 · IC025 +5.7 3/3 methods agree | Not in label — unassessed | serious n=48 · ♀ 100% (drug 68%) · 100% clinician | no trial arm names this drug |
| Helicobacter infection | 1,478 | 294.0 279.0–309.8ROR 334.7 · χ² 368,102 / p <1e-300 | 250.1 EB05 239.6 · IC025 +7.8 3/3 methods agree | Not in label — unassessed | serious PRR 165.5 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Folliculitis | 1,447 | 282.4 267.9–297.7ROR 320.6 · χ² 348,119 / p <1e-300 | 241.7 EB05 231.4 · IC025 +7.7 3/3 methods agree | Not in label — unassessed | serious PRR 177.7 · ♀ 100% (drug 68%) · 93% clinician | no trial arm names this drug |
| Sleep disorder due to general medical condition, insomnia type | 841 | 260.4 242.7–279.4ROR 279.8 · χ² 188,407 / p <1e-300 | 224.9 EB05 212.5 · IC025 +7.5 3/3 methods agree | Not in label — unassessed | serious n=841 · ♀ 99% (drug 68%) · 90% clinician | no trial arm names this drug |
| Rheumatoid factor positive | 687 | 234.2 216.7–253.2ROR 248.3 · χ² 140,131 / p <1e-300 | 204.9 EB05 192.4 · IC025 +7.4 3/3 methods agree | Lab value / disease marker | serious n=687 · ♀ 100% (drug 68%) · 95% clinician | no trial arm names this drug |
| Pemphigus | 1,430 | 225.2 213.8–237.3ROR 255.3 · χ² 282,008 / p <1e-300 | 198.6 EB05 190.1 · IC025 +7.5 3/3 methods agree | Not in label — unassessed | serious PRR 124.6 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Breast cancer stage iii | 702 | 212.2 196.6–229.0ROR 225.2 · χ² 131,095 / p <1e-300 | 187.9 EB05 176.5 · IC025 +7.3 3/3 methods agree | Not in label — unassessed | serious n=702 · ♀ 100% (drug 68%) · 96% clinician | no trial arm names this drug |
| Hand deformity | 1,406 | 208.6 198.0–219.9ROR 235.9 · χ² 258,867 / p <1e-300 | 185.6 EB05 177.6 · IC025 +7.4 3/3 methods agree | Not in label — unassessed | serious PRR 126.2 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Vascular malformation | 22 | 199.8 128.5–310.6ROR 200.2 · χ² 3,720 / p <1e-300 | 155.1 EB05 108.0 · IC025 +4.5 3/3 methods agree | Not in label — unassessed | serious n=22 · ♀ 100% (drug 68%) | no trial arm names this drug |
| Retinitis | 171 | 197.7 168.9–231.4ROR 200.5 · χ² 29,816 / p <1e-300 | 173.9 EB05 153.1 · IC025 +6.6 3/3 methods agree | Not in label — unassessed | serious n=171 · ♀ 100% (drug 68%) · 91% clinician | no trial arm names this drug |
| C-reactive protein abnormal | 638 | 191.6 176.9–207.5ROR 202.2 · χ² 108,617 / p <1e-300 | 171.5 EB05 160.6 · IC025 +7.1 3/3 methods agree | Lab value / disease marker | serious n=638 · ♀ 100% (drug 68%) · 93% clinician | no trial arm names this drug |
| Paranasal cyst | 22 | 174.7 112.7–270.8ROR 175.0 · χ² 3,291 / p <1e-300 | 139.6 EB05 97.2 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious n=22 · ♀ 100% (drug 68%) | no trial arm names this drug |
| Pericarditis | 1,428 | 162.3 154.2–170.9ROR 183.9 · χ² 209,117 / p <1e-300 | 148.0 EB05 141.7 · IC025 +7.1 3/3 methods agree | Not in label — unassessed | serious PRR 93.3 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Porphyria acute | 115 | 157.3 130.1–190.3ROR 158.8 · χ² 16,215 / p <1e-300 | 140.8 EB05 120.5 · IC025 +6.2 3/3 methods agree | Not in label — unassessed | serious n=115 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Blepharospasm | 512 | 155.7 142.5–170.2ROR 162.6 · χ² 72,021 / p <1e-300 | 142.1 EB05 132.0 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious n=510 · ♀ 100% (drug 68%) · 96% clinician | no trial arm names this drug |
| Lip dry | 736 | 155.0 144.0–166.8ROR 165.0 · χ² 103,139 / p <1e-300 | 141.7 EB05 133.3 · IC025 +6.9 3/3 methods agree | Not in label — unassessed | serious n=734 · ♀ 100% (drug 68%) · 96% clinician | no trial arm names this drug |
| Bursitis | 954 | 148.7 139.5–158.5ROR 161.3 · χ² 128,687 / p <1e-300 | 136.5 EB05 129.4 · IC025 +6.9 3/3 methods agree | Not in label — unassessed | serious PRR 100.5 · ♀ 100% (drug 68%) · 96% clinician | no trial arm names this drug |
| Synovitis | 1,392 | 144.7 137.5–152.4ROR 163.4 · χ² 183,211 / p <1e-300 | 133.3 EB05 127.5 · IC025 +6.9 3/3 methods agree | Not in label — unassessed | serious PRR 87.2 · ♀ 99% (drug 68%) · 92% clinician | no trial arm names this drug |
| Onychomadesis | 309 | 139.1 124.1–156.0ROR 142.8 · χ² 39,064 / p <1e-300 | 127.7 EB05 116.2 · IC025 +6.5 3/3 methods agree | Not in label — unassessed | serious n=309 · ♀ 100% (drug 68%) · 98% clinician | no trial arm names this drug |
Trial evidence (ClinicalTrials.gov)
ClinicalTrials.gov returned results-bearing trials mentioning Acetaminophen and Codeine only as a background or rescue medication (NCT03472469, NCT04452344); 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 |
|---|---|---|---|---|---|---|
| Dependence | 3,690 | 123.2 119.8–126.7ROR 176.8 · χ² 418,192 / p <1e-300 | 114.9 EB05 111.8 · IC025 +6.8 3/3 methods agree | Not in label — unassessed | serious PRR 72.2 · ♀ 45% (drug 68%) · 100% consumer | no trial arm names this drug |
| Overdose | 2,125 | 17.1 16.5–17.8ROR 20.6 · χ² 32,300 / p <1e-300 | 17.0 EB05 16.4 · IC025 +4.0 3/3 methods agree | Reporting / coding artifact | serious PRR 13.3 · ♀ 47% (drug 68%) · 90% consumer | no trial arm names this drug |
| Pain | 2,058 | 5.8 5.6–6.0ROR 6.8 · χ² 8,404 / p <1e-300 | 5.8 EB05 5.6 · IC025 +2.5 3/3 methods agree | Likely indication confounding term in indications; also in warnings | serious PRR 5.5 · ♀ 92% (drug 68%) | no trial arm names this drug |
| Fatigue (tiredness) | 1,995 | 4.5 4.3–4.6ROR 5.1 · χ² 5,533 / p <1e-300 | 4.4 EB05 4.3 · IC025 +2.1 3/3 methods agree | Not in label — unassessed | serious PRR 5.1 · ♀ 95% (drug 68%) | no trial arm names this drug |
| Drug ineffective (drug did not work) | 1,990 | 2.6 2.5–2.7ROR 2.9 · χ² 2,120 / p <1e-300 | 2.6 EB05 2.5 · IC025 +1.3 3/3 methods agree | Reporting / coding artifact | serious PRR 4.4 · ♀ 93% (drug 68%) | no trial arm names this drug |
| Arthralgia (joint pain) | 1,785 | 7.5 7.2–7.8ROR 8.6 · χ² 10,183 / p <1e-300 | 7.4 EB05 7.2 · IC025 +2.8 3/3 methods agree | Not in label — unassessed | serious PRR 8.4 · ♀ 96% (drug 68%) | no trial arm names this drug |
| Rheumatoid arthritis | 1,686 | 26.2 25.0–27.4ROR 30.3 · χ² 40,432 / p <1e-300 | 25.8 EB05 24.8 · IC025 +4.6 3/3 methods agree | Likely indication confounding shares a disease stem with the indications wording | serious PRR 19.7 · ♀ 99% (drug 68%) · 92% clinician | no trial arm names this drug |
| Off label use (used outside approved label) | 1,673 | 3.3 3.2–3.5ROR 3.7 · χ² 2,856 / p <1e-300 | 3.3 EB05 3.2 · IC025 +1.7 3/3 methods agree | Reporting / coding artifact | serious PRR 3.8 · ♀ 93% (drug 68%) | no trial arm names this drug |
| Rash | 1,647 | 6.6 6.3–6.9ROR 7.5 · χ² 7,951 / p <1e-300 | 6.6 EB05 6.3 · IC025 +2.6 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 9.0 · ♀ 97% (drug 68%) | no trial arm names this drug |
| Joint swelling | 1,601 | 23.3 22.3–24.4ROR 26.7 · χ² 33,895 / p <1e-300 | 23.0 EB05 22.1 · IC025 +4.4 3/3 methods agree | Not in label — unassessed | serious PRR 24.6 · ♀ 98% (drug 68%) · 90% clinician | no trial arm names this drug |
| Confusional state (confusion) | 1,600 | 17.3 16.5–18.1ROR 19.7 · χ² 24,454 / p <1e-300 | 17.1 EB05 16.4 · IC025 +4.0 3/3 methods agree | Not in label — unassessed | serious PRR 13.6 · ♀ 97% (drug 68%) · 91% clinician | no trial arm names this drug |
| Arthropathy | 1,515 | 48.3 46.1–50.7ROR 55.1 · χ² 68,408 / p <1e-300 | 47.0 EB05 45.0 · IC025 +5.4 3/3 methods agree | Not in label — unassessed | serious PRR 35.7 · ♀ 99% (drug 68%) · 91% clinician | no trial arm names this drug |
| Blister | 1,511 | 48.0 45.7–50.3ROR 54.7 · χ² 67,730 / p <1e-300 | 46.7 EB05 44.7 · IC025 +5.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 48.1 · ♀ 99% (drug 68%) · 93% clinician | no trial arm names this drug |
| Hepatic enzyme increased | 1,502 | 39.1 37.3–41.0ROR 44.5 · χ² 54,677 / p <1e-300 | 38.2 EB05 36.6 · IC025 +5.2 3/3 methods agree | Lab value / disease marker | serious PRR 34.4 · ♀ 100% (drug 68%) · 92% clinician | no trial arm names this drug |
| Nasopharyngitis (common cold) | 1,498 | 14.1 13.5–14.8ROR 16.0 · χ² 18,300 / p <1e-300 | 14.0 EB05 13.4 · IC025 +3.7 3/3 methods agree | Not in label — unassessed | serious PRR 19.4 · ♀ 99% (drug 68%) · 91% clinician | 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.
- Hepatic enzyme — n=40, PRR 696.9
- Subcutaneous drug absorption impaired — n=144, PRR 624.0
- Facet joint syndrome — n=779, PRR 570.1
- Vaginal flatulence — n=67, PRR 486.8
- Duodenal ulcer perforation — n=1,491, PRR 442.4
- Swollen joint count — n=48, PRR 420.3
- Deep vein thrombosis postoperative — n=382, PRR 419.7
- Adjustment disorder with depressed mood — n=391, PRR 417.5
- Rheumatic fever — n=822, PRR 402.2
- Lupus vulgaris — n=214, PRR 380.2
✓ A hand-written Bradford Hill causality assessment exists for this drug: Acetaminophen (paracetamol) ↔ Liver injury / hepatotoxicity.
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 Acetaminophen and Codeine?
In FDA FAERS, the most frequently co-reported reaction terms for Acetaminophen and Codeine are dependence, pain, fatigue, arthralgia, rheumatoid arthritis, rash. 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 Acetaminophen and Codeine have an FDA boxed warning?
No. The FDA label retrieved for Acetaminophen and Codeine has no boxed warning; see the label's Warnings and Precautions for the recognised risks.
Do FAERS signals prove that Acetaminophen and Codeine 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 004c39cd-b4f4-1cae-e063-6394a90a0697, effective 20251003; matched on
openfda.generic_name.exact:"ACETAMINOPHEN") - 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, 1,066 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
ACETAMINOPHEN, results-bearing studies sorted by enrollment)
Page generated 2026-10-08. 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.