Common Side Effects and Their Incidence
Icosapent ethyl (Vascepa), used to lower triglycerides, has side effects reported in clinical trials like REDUCE-IT. The most frequent is bleeding, occurring in 2.7% of patients on 4g/day versus 2.1% on placebo—a 0.6% absolute increase.[1][2] Gout or arthralgia affected 3.1% versus 2.3% (0.8% increase).[1] Non-serious bleeding events, like epistaxis, were more common but low overall.3
How Often Do Serious Side Effects Happen?
Serious bleeding was rare at 0.8% (icosapent ethyl) versus 0.7% (placebo).[1] Atrial fibrillation occurred in 5.3% versus 3.9% (1.4% increase), linked to cardiovascular risk factors rather than the drug alone.2 No significant rises in stroke, heart failure, or cancer were seen.[1]
What Patients Report Most Frequently
In REDUCE-IT (8,179 patients), musculoskeletal pain hit 12.1% versus 11.0%; diarrhea 8.2% versus 7.3%; constipation 5.0% versus 4.6%. These were mostly mild and balanced with placebo, suggesting they're not strongly drug-attributable.1 Post-marketing, allergic reactions and myalgia appear occasionally but lack precise rates.[2]
Differences by Dose or Patient Group
At 2g/day (ANCHOR trial), side effects mirrored placebo more closely, with bleeding at 1.9% versus 1.3%.3 Elderly patients or those on antiplatelets saw slightly higher bleeding risk (up to 1% absolute increase).[2] No major sex or race differences noted.[1]
Comparison to Placebo and Other Fish Oils
Placebo-adjusted rates stay under 2% for key events, far below EPA/DHA combos like Lovaza (higher GI issues at 5-10%).3 REDUCE-IT showed cardiovascular benefits outweighed risks.[1]
[1]: https://www.nejm.org/doi/full/10.1056/NEJMoa1812792 (REDUCE-IT trial)
[2]: https://www.accessdata.fda.gov/drugsatfda_docs/label/2020/202057s019lbl.pdf (FDA label)