What the label lists and what reports show
Romiplostim side effects
Romiplostim's FDA label: “In adult patients, the most common adverse reactions (≥ 5% higher patient incidence in Nplate versus placebo) are arthralgia, dizziness, insomnia, myalgia, pain in extremity, abdominal pain, shoulder pain, dyspepsia, and paresthesia.” FAERS holds 14,968 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 platelet count decreased (1,744 reports).
- No generic listed
Check it at the source: the romiplostim FDA label on DailyMed (effective June 23, 2026, Amgen, Inc); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of Nplate?Nplate may cause serious side effects. See “What is the most important information I should know about Nplate?” The most common side effects of Nplate in adults include: • headache • tingling or numbness in hands and feet • joint pain • bronchitis • dizziness • inflammation of the sinuses (sinusitis) • trouble sleeping • vomiting • muscle tenderness or weakness • pain in the arms and legs • stomach (abdomen) pain • shoulder pain • indigestion • diarrhea • upper respiratory tract infection • cough • nausea • pain in mouth and throat (oropharyngeal pain) The most common side effects of Nplate in children 1 year of age and older include: • bruising • upper respiratory tract infection • pain in mouth and throat (oropharyngeal pain) People who take Nplate may have an increased risk of developing new or worsening changes in the bone marrow called “increased reticulin”. […]
Source: FDA drug label, Amgen, Inc, effective June 23, 2026 (SPL set c45f9a58-37c1-4f76-8e36-97d38c577037), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsIn adult patients, the most common adverse reactions (≥ 5% higher patient incidence in Nplate versus placebo) are arthralgia, dizziness, insomnia, myalgia, pain in extremity, abdominal pain, shoulder pain, dyspepsia, and paresthesia.
Table 4. Common Adverse Reactions (≥ 5% Incidence and ≥ 5% More Frequent on the Nplate Arm) from Two Placebo-Controlled Trials in Pediatric Patients with ITP for at least 6 months
| Adverse Reactions by Body System | Nplate (%) (N = 59) | Placebo (%) (N = 24) |
|---|---|---|
| Upper Respiratory Tract Infection | 18 (31%) | 6 (25%) |
| Ear Infection | 3 (5%) | 0 |
| Gastroenteritis | 3 (5%) | 0 |
| Sinusitis | 3 (5%) | 0 |
| Oropharyngeal Pain | 15 (25%) | 1 (4%) |
| Diarrhea | 12 (20%) | 3 (13%) |
| Abdominal Pain Upper | 8 (14%) | 1 (4%) |
| Rash | 9 (15%) | 2 (8%) |
| Purpura | 4 (7%) | 0 |
| Urticaria | 3 (5%) | 0 |
| Pyrexia | 14 (24%) | 2 (8%) |
| Peripheral Swelling | 4 (7%) | 0 |
| Contusion | 24 (41%) | 8 (33%) |
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 clinically significant adverse reactions are discussed in greater detail in other sections: Progression of Myelodysplastic Syndromes [see Warnings and Precautions ( 5.1 )] Thrombotic/Thromboembolic Complications [see Warnings and Precautions ( 5.2 )] Loss of Response to Nplate [see Warnings and Precautions ( 5.3 )] In adult patients, the most common adverse reactions (≥ 5% higher patient incidence in Nplate versus placebo) are arthralgia, dizziness, insomnia, myalgia, pain in extremity, abdominal pain, shoulder pain, dyspepsia, and paresthesia. Headache was the most commonly reported adverse reaction that did not occur at ≥ 5% higher patient incidence in Nplate versus placebo. ( 6.1 ) In pediatric patients, the most common adverse reactions (≥ 25%) are: contusion, upper respiratory tract infection, and oropharyngeal pain. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Amgen Inc. at 1-800-77-AMGEN (1-800-772-6436) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, 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. …
Source: FDA drug label, Amgen, Inc, effective June 23, 2026 (SPL set c45f9a58-37c1-4f76-8e36-97d38c577037), via openFDA; the full label on DailyMed
What do FAERS reports show?
14,968 reports list romiplostim among the medicines taken, each a report of something that happened, not proof the medicine caused it; 2,626 are coded as a death and 3,845 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 20 reactions below, 8 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?
- Romiplostim: 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