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Phenylbutazone Side Effects

The most commonly reported side effects of phenylbutazone include drug hypersensitivity, hypersensitivity, and completed suicide, based on 311 FDA adverse event reports from 2004 to 2025. 8.0% of reports found the drug to be ineffective.

Phenylbutazone side effects

Percentages show how often each reaction appears relative to total reports for phenylbutazone.

1
Drug Hypersensitivity9.6%30
2
Hypersensitivity8.0%25
3
Drug Ineffective8.0%25
4
Completed Suicide7.4%23
5
Abdominal Distension7.1%22
6
Arthralgia6.8%21
7
Anaphylactic Reaction6.8%21
8
Eructation6.8%21
9
Oropharyngeal Discomfort6.8%21
10
Barrett^s Oesophagus6.8%21
11
Vitamin B12 Deficiency6.8%21
12
Dyspepsia6.8%21
13
Neck Pain6.8%21
14
Regurgitation6.8%21
15
Inflammation6.4%20

These are voluntary reports and do not establish that phenylbutazone caused these reactions.

Report severity

92.9%Serious289 reports
38.3%Hospitalizations119 reports
24.8%Fatal77 reports

Seriousness is determined by the reporter, not by OpenClaim.

Phenylbutazone drug interactions

Other drugs that appear in adverse event reports alongside phenylbutazone. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Etanercept13.8%43
2
Infliximab13.2%41
3
Acetaminophen10.9%34
4
Metformin10.9%34
5
Methotrexate10.0%31
6
Dexamethasone9.6%30
7
Ondansetron9.0%28
8
Leflunomide9.0%28
9
Adalimumab8.7%27
10
Calcium8.0%25
11
Thiamine7.7%24
12
Aprepitant7.7%24
13
Cisplatin7.7%24
14
Nicotine7.7%24
15
Etoposide7.7%24

Taken alongside

1
Acetaminophen7.4%23
2
Prednisone7.1%22
3
Omeprazole6.8%21
4
Azathioprine6.8%21
5
Prednisolone6.4%20
6
Cyclosporine6.4%20
7
Penicillamine6.4%20
8
Minocycline-hydrochloride6.1%19
9
Tocilizumab5.8%18
10
Methotrexate4.8%15
11
Metformin4.2%13
12
Atorvastatin-calcium3.5%11
13
Furosemide3.5%11
14
Tramadol-hydrochloride3.2%10
15
Levothyroxine-sodium2.9%9

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports phenylbutazone side effects

46.6% of phenylbutazone adverse event reports involve female patients and 42.8% involve male patients. The largest age group is adult at 73%. These figures reflect who reports side effects, not underlying risk.

Sex

Female46.6%
Male42.8%
Unknown10.6%

Age group

< 20.4%
2–110.9%
12–170.4%
18–6473.2%
65+25.1%

What is phenylbutazone used for

Conditions and purposes for which patients were taking phenylbutazone when the adverse event was reported.

Abdominal Pain UpperAnkylosing SpondylitisArginase IncreasedArthralgiaArthritisAntibiotic TherapyArthritisBack PainBack PainBlood CholesterolCompleted SuicideDiuretic TherapyDrug Use For Unknown IndicationGastrointestinal Somatic Symptom DisorderHyperglycaemia

Showing 15 of 34 indications

Phenylbutazone brand names and reporting trend

Phenylbutazone is sold under the brand name Azolid.

Brand names

Azolid236

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking phenylbutazone with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.