Eltrombopag is an oral medicine that helps the body produce more platelets, the blood cells responsible for clotting. It belongs to a class of medicines called thrombopoietin receptor agonists, used to treat certain types of low platelet counts (thrombocytopenia) and, in combination with other therapy, severe aplastic anemia. It is a prescription-only medicine that carries a boxed warning.

• Therapeutic Class: Platelet-stimulating agent.

• Pharmacological Class: Thrombopoietin (TPO) receptor agonist.

• Drug Family: Non-peptide TPO receptor agonists.

• ATC Classification: B02BX05 (Eltrombopag).

Approved: Thrombocytopenia in adults and pediatric patients (1 year and older) with chronic immune (idiopathic) thrombocytopenic purpura (ITP) who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy; thrombocytopenia in patients with chronic hepatitis C to allow initiation and maintenance of interferon-based therapy; and first-line treatment of severe aplastic anemia in combination with standard immunosuppressive therapy.

Commonly used for: Patients with chronic ITP whose platelet counts remain low despite standard treatments, and patients with severe aplastic anemia receiving immunosuppressive therapy.

Off-label use (only under medical guidance): Sometimes studied or used for thrombocytopenia related to other conditions (e.g., myelodysplastic syndrome, chemotherapy-induced thrombocytopenia) under specialist guidance.

● Oral tablets: 12.5 mg, 25 mg, 50 mg, and 75 mg.

● Oral suspension: for patients unable to swallow tablets, particularly younger children.

Eltrombopag attaches to the thrombopoietin receptor on bone marrow cells, mimicking the action of the body's natural hormone (thrombopoietin) that stimulates platelet production. This signals the bone marrow to produce more platelet-forming cells (megakaryocytes), increasing the number of platelets released into the bloodstream.

• Standard starting dose (ITP, general adult population): 50 mg once daily, adjusted to the lowest dose that achieves and maintains a platelet count of at least 50 x 10^9/L, not exceeding 75 mg/day.

• Condition-wise dose: Reduced starting dose (25 mg once daily) in patients of East/Southeast Asian ancestry and in those with hepatic impairment; different reduced starting doses apply for chronic hepatitis C-associated thrombocytopenia and severe aplastic anemia, per product labelling.

• Route: Oral, taken on an empty stomach (1 hour before or 2 hours after a meal), with at least a 4-hour gap from antacids, dairy products, or supplements containing calcium, iron, aluminum, magnesium, selenium, or zinc.

• Missed dose: Take as soon as remembered unless close to the next dose; don't double up.

• Overdose: Can cause excessive platelet counts and increased clotting risk, or liver toxicity; requires urgent medical attention.

• Common: Nausea, diarrhoea, headache, and elevated liver enzymes.

• Serious: Severe liver injury (hepatotoxicity), increased risk of blood clots (thrombotic/thromboembolic events), cataracts, and, in patients with myelodysplastic syndrome, a risk of disease progression.

• Emergency symptoms: Yellowing of the skin/eyes, dark urine, unusual tiredness, right upper abdominal pain, or signs of a blood clot (leg swelling/pain, chest pain, sudden shortness of breath).

• Recovery advice: Regular liver function tests and platelet counts allow the dose to be adjusted before problems become serious; the medicine is not intended to normalise platelet counts completely, only to reduce bleeding risk to a safer level.

• Pregnancy: Data are insufficient to assess risk; used only if clearly needed, under medical guidance.

• Breastfeeding: Discussed with the treating doctor given limited safety data.

• Liver disease: Requires reduced starting dose and closer monitoring; a key focus of the boxed warning.

• Kidney disease: No specific dose adjustment generally required, though used with routine monitoring.

• Elderly: Used with routine monitoring; no specific age-based dose adjustment beyond general precautions.

• Children: Approved for ITP in children 1 year and older, and for severe aplastic anemia in children 2 years and older, with weight/age-based dosing.

● Antacids, dairy products, and mineral supplements (calcium, iron, aluminium, magnesium, selenium, zinc): significantly reduce eltrombopag absorption; dosing must be separated by several hours.

● Statins and other OATP1B1/BCRP substrate drugs: eltrombopag can increase levels of these medicines, requiring dose adjustment or closer monitoring.

● Strong CYP1A2/2C8 inhibitors or inducers: may alter eltrombopag levels.

● Interferon and ribavirin (in chronic hepatitis C use): combined use requires close monitoring for hepatic decompensation, per the boxed warning.

● Liver function tests before starting and regularly during treatment.

● Complete blood counts, particularly platelet counts, weekly until a stable level is achieved, then monthly.

● Eye examinations periodically, given the reported risk of cataracts.

● Monitoring for signs of blood clots throughout treatment.

Romiplostim (another thrombopoietin receptor agonist, given by injection), Fostamatinib (different mechanism, a spleen tyrosine kinase inhibitor), Avatrombopag (another oral TPO receptor agonist).

Used alongside standard immunosuppressive therapy (e.g., horse antithymocyte globulin and cyclosporine) as first-line treatment for severe aplastic anemia; used alongside interferon-based antiviral therapy specifically for chronic hepatitis C-associated thrombocytopenia.

● Immune Thrombocytopenia (ITP) Medicines

● Severe Aplastic Anemia Treatments

● Thrombopoietin Receptor Agonists

1. 7 Unexpected Warning Signs of Iron Deficiency

2. Low Haemoglobin: Sign, Symptoms, Causes & Treatment

1. https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/022291s041,207027s020lbl.pd

2. https://reference.medscape.com/drug/promacta-alvaiz-eltrombopag-342178

The information on this page is for educational purposes only and is not a substitute for medical advice. Please consult your oncologist to know if this treatment is appropriate for your condition.