Clopidogrel vs Clopidogrel Bisulfate: side effects in FDA adverse event reports
At a glance
| Clopidogrel | Clopidogrel Bisulfate | |
|---|---|---|
| Drug class | – | – |
| Brand names | – | – |
| FAERS reports | 197,000 | 101,649 |
| Serious | 81% | 86% |
| Death outcome | 21,779 | 11,097 |
| Boxed warning | Yes DIMINISHED EFFECTIVENESS IN POOR METABOLIZERS The effectiveness of clopidogrel is dependent on its activation to an active metabolite by the cytochrome P450 (CY | Yes DIMINISHED ANTIPLATELET EFFECT IN PATIENTS WITH TWO LOSS-OF-FUNCTION ALLELES OF THE CYP2C19 GENE See full prescribing information for complete boxed warning. Ef |
Signals both drugs share
| Reaction | Clopidogrel | Clopidogrel Bisulfate | Label screen (A / B) |
|---|---|---|---|
| Retroperitoneal haemorrhage | 253 · PRR 12.0 | 161 · PRR 14.3 | Labeled adverse reaction / Not in label — unassessed |
| Blood loss anaemia | 216 · PRR 11.3 | 187 · PRR 18.8 | Labeled (related wording) / Labeled (related wording) |
| Retroperitoneal haematoma | 229 · PRR 12.3 | 167 · PRR 16.9 | Labeled (related wording) / Not in label — unassessed |
| Melaena | 1,995 · PRR 10.5 | 1,562 · PRR 15.7 | Not in label — unassessed / Not in label — unassessed |
| Vascular stent thrombosis | 642 · PRR 48.9 | 641 · PRR 95.0 | Not in label — unassessed / Not in label — unassessed |
| Coronary artery stenosis | 700 · PRR 17.0 | 410 · PRR 18.2 | Likely indication confounding / Likely indication confounding |
| Thrombosis in device | 544 · PRR 20.8 | 370 · PRR 25.9 | Not in label — unassessed / Not in label — unassessed |
| Nephrogenic anaemia | 576 · PRR 14.8 | 329 · PRR 15.6 | Not in label — unassessed / Not in label — unassessed |
| Hyperparathyroidism secondary | 336 · PRR 16.2 | 192 · PRR 16.9 | Not in label — unassessed / Not in label — unassessed |
| Vascular pseudoaneurysm | 291 · PRR 21.1 | 212 · PRR 28.4 | Not in label — unassessed / Not in label — unassessed |
| Coronary artery thrombosis | 258 · PRR 15.4 | 157 · PRR 17.3 | Likely indication confounding / Likely indication confounding |
| Coronary artery restenosis | 173 · PRR 42.7 | 89 · PRR 35.7 | Likely indication confounding / Likely indication confounding |
| Extradural haematoma | 141 · PRR 12.5 | 118 · PRR 20.0 | Not in label — unassessed / Not in label — unassessed |
| Spinal epidural haematoma | 123 · PRR 29.5 | 136 · PRR 65.4 | Not in label — unassessed / Not in label — unassessed |
| Arterial haemorrhage | 131 · PRR 13.6 | 119 · PRR 23.7 | Likely indication confounding / Likely indication confounding |
| Chronic kidney disease-mineral and bone disorder | 150 · PRR 17.1 | 81 · PRR 16.7 | Not in label — unassessed / Not in label — unassessed |
| Peripheral artery occlusion | 129 · PRR 10.7 | 90 · PRR 14.1 | Not in label — unassessed / Not in label — unassessed |
| Mallory-weiss syndrome | 122 · PRR 11.2 | 81 · PRR 14.0 | Not in label — unassessed / Not in label — unassessed |
| Carotid arteriosclerosis | 115 · PRR 13.4 | 81 · PRR 17.6 | Likely indication confounding / Likely indication confounding |
Labeled signals distinctive to Clopidogrel
- Gastrointestinal haemorrhage — n=8,285, PRR 11.5 Labeled adverse reaction
- Upper gastrointestinal haemorrhage — n=1,605, PRR 11.1 Labeled (related wording)
- Ulcer haemorrhage — n=998, PRR 18.3 Labeled (related wording)
- Acute coronary syndrome — n=774, PRR 10.8 Labeled — boxed warning
- Thrombotic thrombocytopenic purpura — n=456, PRR 15.7 Labeled — boxed warning
- Diverticulum intestinal haemorrhagic — n=249, PRR 13.0 Labeled (related wording)
Labeled signals distinctive to Clopidogrel Bisulfate
- Respiratory tract haemorrhage — n=84, PRR 33.6 Labeled (related wording)
- Insulin autoimmune syndrome — n=82, PRR 64.6 Labeled adverse reaction
- Acquired haemophilia — n=78, PRR 17.6 Labeled adverse reaction
Common questions
Which has more reported side effects, Clopidogrel or Clopidogrel Bisulfate?
Clopidogrel has 197,000 FAERS reports and Clopidogrel Bisulfate 101,649. More reports does not mean more dangerous: volume follows how widely and how long a drug has been used, prescription vs over-the-counter status, and publicity. The seriousness share (81% vs 86%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Clopidogrel and Clopidogrel Bisulfate share?
Both drugs carry disproportionality signals for retroperitoneal haemorrhage, blood loss anaemia, retroperitoneal haematoma, melaena, vascular stent thrombosis. Shared signals often reflect a shared drug class or the condition both are used for.
Is Clopidogrel or Clopidogrel Bisulfate safer?
FAERS cannot answer that: it has no denominator and no comparator. Use this page to see which risks are already on each label and which signals are unlabeled, then check the prescribing information and your clinician for your situation.
Sources: openFDA FAERS pair statistics (OpenPV build 2026-09-14), FDA labels via openFDA, openFDA count queries for seriousness and deaths. Pair chosen because it is a commonly searched comparison. Generated 2026-10-08.