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Cefaclor Side Effects

The most commonly reported side effects of cefaclor include drug hypersensitivity, vomiting, and nausea, based on 2,357 FDA adverse event reports from 2004 to 2025. 4.8% of reports found the drug to be ineffective.

Cefaclor side effects

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

1
Drug Hypersensitivity27.3%643
2
Vomiting7.7%181
3
Nausea7.3%173
4
Infection7.3%173
5
Drug Intolerance7.0%165
6
Fatigue6.7%157
7
International Normalised Ratio Fluctuation6.6%155
8
Therapeutic Product Effect Incomplete5.3%126
9
Drug Ineffective4.8%112
10
Rash4.6%109
11
Hypersensitivity4.5%106
12
Dizziness4.4%103
13
Bloody Discharge4.4%103
14
Diarrhoea4.2%100
15
Pyrexia4.2%99

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

Report severity

73.4%Serious1,730 reports
37.0%Hospitalizations871 reports
7.8%Fatal183 reports

Seriousness is determined by the reporter, not by OpenClaim.

Cefaclor drug interactions

Other drugs that appear in adverse event reports alongside cefaclor. 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
Levofloxacin11.3%267
2
Erythromycin10.7%252
3
Prednisone10.3%242
4
Adalimumab8.5%200
5
Metronidazole8.1%191
6
Methotrexate8.0%189
7
Celecoxib8.0%189
8
Meperidine-hydrochloride7.4%175
9
Hydroxychloroquine-sulfate7.4%175
10
Diclofenac7.1%167
11
Sulfasalazine7.0%165
12
Pregabalin7.0%165
13
Leflunomide7.0%165
14
Misoprostol6.4%152
15
Norfloxacin6.4%152

Taken alongside

1
Acetaminophen12.3%291
2
Omeprazole9.4%221
3
Aspirin8.6%202
4
Furosemide8.6%202
5
Albuterol7.3%172
6
Amoxicillin6.0%141
7
Prednisone5.9%138
8
Sulfamethoxazole5.6%131
9
Ibuprofen5.4%128
10
Levofloxacin5.3%126
11
Promethazine-hydrochloride5.3%126
12
Potassium-chloride5.3%125
13
Methylprednisolone5.3%124
14
Ranitidine5.2%122
15
Atorvastatin-calcium5.0%117

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 cefaclor side effects

60.4% of cefaclor adverse event reports involve female patients and 29.1% involve male patients. The largest age group is adult at 54%. These figures reflect who reports side effects, not underlying risk.

Sex

Female60.4%
Male29.1%
Unknown10.5%

Age group

< 25.2%
2–118.8%
12–172.2%
18–6454.4%
65+29.4%

What is cefaclor used for

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

Abdominal PainAcneAcute SinusitisAcute TonsillitisAdverse EventAnalgesic TherapyAnimal BiteAnti-infective TherapyAntibiotic Associated ColitisAntibiotic LevelAntibiotic ProphylaxisAntibiotic TherapyAntiinflammatory TherapyArthralgiaArthritis Bacterial

Showing 15 of 219 indications

Cefaclor brand names and reporting trend

Cefaclor is sold under the brand name Ceclor.

Brand names

Ceclor1,831

Quarterly reports (20042025)

20052010201520202025

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

Taking cefaclor with another medication?

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