What the label lists and what reports show
Etonogestrel side effects
Etonogestrel's FDA label: “Most common (≥10%) adverse reactions reported in clinical trials were change in menstrual bleeding pattern, headache, vaginitis, weight increase, acne, breast pain, abdominal pain, and pharyngitis.” FAERS holds 47,446 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 complication associated with device (5,304 reports).
- No generic listed
- Boxed warning
Check it at the source: the etonogestrel FDA label on DailyMed (effective May 28, 2026, Organon LLC); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the most common side effects I can expect while using NEXPLANON?Changes in Menstrual Bleeding Patterns (Menstrual Periods) The most common side effect of NEXPLANON is a change in your normal menstrual bleeding pattern. In studies, one out of ten women stopped using the implant because of an unfavorable change in their bleeding pattern. You may experience longer or shorter bleeding during your periods or have no bleeding at all. The time between periods may vary, and you may also have spotting in between periods. […]
Source: FDA drug label, Organon LLC, effective May 28, 2026 (SPL set 487f8a62-e142-457c-97cc-2e398fde7594), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsMost common (≥10%) adverse reactions reported in clinical trials were change in menstrual bleeding pattern, headache, vaginitis, weight increase, acne, breast pain, abdominal pain, and pharyngitis.
Table 4: Common Adverse Reactions Reported by ≥5% of Subjects in 3-Year Clinical Trials with the Non-Radiopaque Etonogestrel Implant (IMPLANON)
| Adverse Reactions | All Studies N = 942 |
|---|---|
| Headache | 24.9% |
| Vaginitis | 14.5% |
| Weight increase | 13.7% |
| Acne | 13.5% |
| Breast pain | 12.8% |
| Abdominal pain | 10.9% |
| Pharyngitis | 10.5% |
| Leukorrhea | 9.6% |
| Influenza-like symptoms | 7.6% |
| Dizziness | 7.2% |
| Dysmenorrhea | 7.2% |
| Back pain | 6.8% |
| Emotional lability | 6.5% |
| Nausea | 6.4% |
| Pain | 5.6% |
| Nervousness | 5.6% |
| Depression | 5.5% |
| Hypersensitivity | 5.4% |
| Insertion site pain | 5.2% |
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 adverse reactions reported with the use of hormonal contraception are discussed elsewhere in the labeling: Changes in Menstrual Bleeding Patterns [see Warnings and Precautions (5.3) ] Ectopic Pregnancies [see Warnings and Precautions (5.4) ] Thrombotic and Other Vascular Events [see Warnings and Precautions (5.5) ] Liver Disease [see Warnings and Precautions (5.8) ] Most common (≥10%) adverse reactions reported in clinical trials were change in menstrual bleeding pattern, headache, vaginitis, weight increase, acne, breast pain, abdominal pain, and pharyngitis. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Organon USA LLC, a subsidiary of Organon & Co., at 1-844-674-3200 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice, because clinical trials are conducted under widely varying conditions. In clinical trials of three years duration involving 942 women who were evaluated for safety, change in menstrual bleeding patterns (irregular menses) was the most common adverse reaction causing discontinuation of use of the non-radiopaque etonogestrel implant (IMPLANON) (11.1% of women). …
Source: FDA drug label, Organon LLC, effective May 28, 2026 (SPL set 487f8a62-e142-457c-97cc-2e398fde7594), via openFDA; the full label on DailyMed
What do FAERS reports show?
47,446 reports list etonogestrel among the medicines taken, each a report of something that happened, not proof the medicine caused it; 109 are coded as a death and 1,686 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 23 reactions below, 3 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?
- Etonogestrel: 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