What the label lists and what reports show
Ertapenem side effects
Ertapenem's FDA label: “The most common adverse reactions (≥5%) in patients treated with INVANZ, including those who were switched to therapy with an oral antimicrobial, were diarrhea, nausea, headache and infused vein complication.” FAERS holds 7,339 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is macular degeneration (808 reports).
- Generic listed
Check it at the source: the ertapenem FDA label on DailyMed (effective February 4, 2026, Merck Sharp & Dohme LLC); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe most common adverse reactions (≥5%) in patients treated with INVANZ, including those who were switched to therapy with an oral antimicrobial, were diarrhea, nausea, headache and infused vein complication.
Table 3 Incidence (%) of Adverse Experiences Reported During Study Therapy Plus 14-Day Follow-Up in ≥2.0% of Adult Patients Treated With INVANZ in Clinical Trials
| Adverse Events | INVANZ Includes Phase IIb/III Complicated intra-abdominal infections, Complicated skin… (N=802) | Piperacillin/ Tazobactam 3.375 g q6h (N=774) | INVANZ Includes Phase IIb/III Community acquired pneumonia and Complicated urinary tract… (N=1152) | Ceftriaxone 1 or 2 g daily (N=942) |
|---|---|---|---|---|
| Infused vein complication | 7.1 | 7.9 | 5.4 | 6.7 |
| Death | 2.5 | 1.6 | 1.3 | 1.6 |
| Edema/swelling | 3.4 | 2.5 | 2.9 | 3.3 |
| Fever | 5.0 | 6.6 | 2.3 | 3.4 |
| Abdominal pain | 3.6 | 4.8 | 4.3 | 3.9 |
| Hypotension | 2.0 | 1.4 | 1.0 | 1.2 |
| Constipation | 4.0 | 5.4 | 3.3 | 3.1 |
| Diarrhea | 10.3 | 12.1 | 9.2 | 9.8 |
| Nausea | 8.5 | 8.7 | 6.4 | 7.4 |
| Vomiting | 3.7 | 5.3 | 4.0 | 4.0 |
| Altered mental status Includes agitation, confusion, disorientation, decreased mental… | 5.1 | 3.4 | 3.3 | 2.5 |
| Dizziness | 2.1 | 3.0 | 1.5 | 2.1 |
| Headache | 5.6 | 5.4 | 6.8 | 6.9 |
| Insomnia | 3.2 | 5.2 | 3.0 | 4.1 |
| Dyspnea | 2.6 | 1.8 | 1.0 | 2.4 |
| Pruritus | 2.0 | 2.6 | 1.0 | 1.9 |
| Rash | 2.5 | 3.1 | 2.3 | 1.5 |
| Vaginitis | 1.4 | 1.0 | 3.3 | 3.7 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following are described in greater detail in the Warnings and Precautions section. Hypersensitivity Reactions [see Warnings and Precautions (5.1) ] Seizure Potential [see Warnings and Precautions (5.2) ] Interaction with Valproic Acid [see Warnings and Precautions (5.3) ] Clostridioides difficile -Associated Diarrhea (CDAD) [see Warnings and Precautions (5.4) ] Caution with Intramuscular Administration [see Warnings and Precautions (5.5) ] Development of Drug-Resistant Bacteria [see Warnings and Precautions (5.6) ] Laboratory Tests [see Warnings and Precautions (5.7) ] Adults: The most common adverse reactions (≥5%) in patients treated with INVANZ, including those who were switched to therapy with an oral antimicrobial, were diarrhea, nausea, headache and infused vein complication. ( 6.1 ) In the prophylaxis indication the overall adverse experience profile was generally comparable to that observed for ertapenem in other clinical trials. ( 6.1 ) Pediatrics: Adverse reactions in this population were comparable to adults. The most common adverse reactions (≥5%) in pediatric patients treated with INVANZ, including those who were switched to therapy with an oral antimicrobial, were diarrhea, vomiting and infusion site pain.
Source: FDA drug label, Merck Sharp & Dohme LLC, effective February 4, 2026 (SPL set 33f3b99b-fa82-42e0-26bf-f49891ae3d22), via openFDA; the full label on DailyMed
What do FAERS reports show?
7,339 reports list ertapenem among the medicines taken, each a report of something that happened, not proof the medicine caused it; 627 are coded as a death and 3,423 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 21 reactions below, 12 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Ertapenem: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions