Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
FOLEX vs AGRYLIN
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Methotrexate, the active ingredient in FOLEX, is a folate analog that inhibits dihydrofolate reductase (DHFR), blocking the conversion of dihydrofolate to tetrahydrofolate, thereby interfering with thymidylate and purine synthesis, leading to inhibition of DNA replication and cell proliferation.
Agrylin (anagrelide) inhibits cyclic nucleotide phosphodiesterase III (PDE3) and reduces platelet production by interfering with megakaryocyte maturation and proliferation, likely via inhibition of cyclic AMP phosphodiesterase and modulation of intracellular calcium levels.
FDA-approved: Treatment of neoplastic diseases (e.g., acute lymphoblastic leukemia, breast cancer, head and neck cancer, non-Hodgkin lymphoma, osteosarcoma),FDA-approved: Treatment of severe psoriasis (adult, recalcitrant, disabling),FDA-approved: Treatment of active rheumatoid arthritis (adult, severe, active) and polyarticular juvenile idiopathic arthritis,Off-label: Management of ectopic pregnancy,Off-label: Treatment of Crohn's disease,Off-label: Management of uveitis
Essential thrombocythemia (ET) to reduce elevated platelet counts and the risk of thrombotic complications
30 mg/m2 intravenously once weekly for 2 weeks followed by a 1-week rest period, or 5-10 mg/m2 intramuscularly or intravenously every 3-4 weeks. For rheumatoid arthritis, 7.5-15 mg orally once weekly.
Adults: 0.5 mg orally once or twice daily, increased by 0.5 mg every 2 weeks to maintain platelet count <600,000/µL. Maximum dose: 10 mg/day.
Terminal half-life: 3-10 hours (mean ~5 hours) for low-dose regimens; higher doses or renal impairment may prolong half-life up to 24 hours.
Terminal elimination half-life: 1.3–1.5 days (31–36 hours) in patients with ET; allows twice-daily dosing.
Methotrexate undergoes hepatic metabolism to polyglutamate metabolites which are retained in cells. It is partially metabolized by aldehyde oxidase and xanthine oxidase. Excretion is primarily renal via glomerular filtration and active tubular secretion.
Primarily metabolized by CYP1A2 to the active metabolite 3-hydroxyanagrelide, and to a lesser extent by CYP2C19 and CYP2D6.
Primarily renal excretion of unchanged drug: ~80-90% within 24 hours. Biliary/fecal excretion accounts for <10%.
Renal: 80% (primarily unchanged drug), Biliary/Fecal: 5%
Approximately 50% bound to serum proteins, primarily albumin.
82–88% bound to plasma proteins (primarily albumin).
Vd: 0.4-0.8 L/kg (total body water), indicating extensive tissue distribution; higher in pleural effusions or ascites.
30–36 L (approximately 0.45–0.5 L/kg for a 70 kg adult); indicates extensive tissue distribution.
Oral bioavailability: dose-dependent, variable (20-80%, higher with low doses); IM: complete but slower absorption; IV: 100%.
Oral: 65–80% (median 73%)
GFR >50 m L/min: no adjustment; GFR 10-50 m L/min: reduce dose by 50%; GFR <10 m L/min: avoid use or reduce dose by 75%.
No specific GFR-based recommendations; use with caution in renal impairment (Cr Cl <50 m L/min) and monitor closely.
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: avoid use.
Child-Pugh A: No adjustment. Child-Pugh B or C: Reduce initial dose by 50% and titrate cautiously.
For acute lymphoblastic leukemia: 12.5 mg/m2 orally once weekly; for juvenile idiopathic arthritis: 10-15 mg/m2 orally or subcutaneously once weekly. Maximum single dose: 20 mg.
Children ≥7 years: 0.5 mg orally once or twice daily; adjust based on platelet response. Maximum: 10 mg/day. Not established for <7 years.
Start at lowest end of dosing range (e.g., 5-7.5 mg orally weekly for rheumatoid arthritis) due to increased risk of toxicity from reduced renal function and folate stores.
No specific adjustment; start at lower end of dosing range (0.5 mg twice daily) and monitor renal function and platelet counts closely.
FOLEX (methotrexate) may cause severe toxicity including death, especially with high doses. Severe reactions include myelosuppression, hepatotoxicity, pulmonary fibrosis, renal failure, and gastrointestinal ulceration. Must be used only by physicians experienced in antimetabolite therapy. Patients should be closely monitored for bone marrow, liver, and renal toxicity.
None
Hepatotoxicity: Risk of acute and chronic liver injury, fibrosis, and cirrhosis, especially with prolonged use or pre-existing liver disease,Myelosuppression: Risk of severe pancytopenia, especially in renal impairment or with concurrent NSAIDs,Pulmonary toxicity: Acute or chronic interstitial pneumonitis, fibrosis,Renal toxicity: Acute renal failure due to precipitation of methotrexate in renal tubules, especially with high doses,Gastrointestinal toxicity: Ulceration, perforation, hemorrhage,Dermatologic reactions: Stevens-Johnson syndrome, toxic epidermal necrolysis,Concurrent NSAIDs increase methotrexate toxicity
Cardiovascular risks: increased risk of ventricular tachycardia, QTc prolongation, and heart failure; use caution in patients with known cardiac disease.,Hematologic effects: monitor complete blood counts regularly due to risk of anemia, leukopenia, or thrombocytopenia.,Hepatic impairment: reduce dose in patients with moderate to severe hepatic impairment.,Renal impairment: use with caution in severe renal impairment.
Hypersensitivity to methotrexate or any component,Breastfeeding,Severe renal impairment (creatinine clearance <10 m L/min),Severe hepatic impairment (e.g., cirrhosis, active hepatitis),Pre-existing severe bone marrow depression (e.g., pancytopenia),Pregnancy (teratogenic and embryotoxic)
Severe hepatic impairment,Known hypersensitivity to anagrelide or any component of the formulation
Avoid alcohol completely; may increase hepatotoxicity. No specific food restrictions, but maintain adequate hydration. Avoid folic acid-rich foods (e.g., fortified cereals, legumes) if combining with leucovorin rescue in high-dose therapy due to potential interference. Take folic acid supplements at a different time than methotrexate if prescribed.
Grapefruit and grapefruit juice should be avoided as they may increase anagrelide plasma concentrations. No other specific dietary restrictions; however, maintain adequate hydration to reduce risk of crystalluria.
FDA Pregnancy Category X. First trimester: High risk of miscarriage, neural tube defects, craniofacial anomalies, and limb defects. Second and third trimesters: Fetal growth restriction, skeletal abnormalities, functional deficits. Avoid use during pregnancy.
Pregnancy Category C. Anagrelide is not recommended in pregnancy. Animal studies have shown embryotoxicity and teratogenicity (e.g., increased fetal resorptions, skeletal anomalies) at doses less than the human therapeutic dose. There are no adequate and well-controlled studies in pregnant women. Use only if potential benefit justifies potential risk to fetus. First trimester: Avoid due to organogenesis risk. Second and third trimesters: Unknown risks; consider alternative therapy.
Contraindicated during breastfeeding. Methotrexate (active component) is excreted in breast milk with an M/P ratio of approximately 0.08; risk of infant accumulation due to long half-life. Do not breastfeed during therapy or for at least 1 week after last dose.
It is not known whether anagrelide is excreted in human milk. No M/P ratio is available. Due to potential for serious adverse reactions in breastfed infants (e.g., thrombocytopenia, cardiovascular effects), advise women not to breastfeed during treatment and for at least 7 days after last dose.
Pregnancy is a contraindication; no dose adjustments are recommended. If used inadvertently, immediate discontinuation and high-dose folic acid rescue. Pharmacokinetic changes in pregnancy (increased Vd and clearance) may require dose reduction if used for non-pregnant patients, but absolute contraindication overrides.
No specific pharmacokinetic studies in pregnancy. Pregnancy-induced plasma volume expansion may lower drug concentrations, potentially requiring dose adjustment to maintain therapeutic effect. However, due to teratogenicity risks, avoid use in pregnancy. If necessary, start at lowest effective dose (0.5 mg/day) and titrate based on platelet count monitoring, not to exceed 10 mg/day.
Folex (methotrexate) is a folate analog antimetabolite used in oncology and autoimmune diseases. Administer leucovorin rescue 24 hours after high-dose methotrexate to prevent severe toxicity. Monitor renal function and methotrexate levels closely. Avoid NSAIDs as they reduce renal clearance and increase toxicity. Hepatotoxicity and pulmonary fibrosis are serious adverse effects. Intrathecal administration requires preservative-free formulation.
Agrylin (anagrelide) is a phosphodiesterase III inhibitor used to reduce platelet counts in essential thrombocythemia. Monitor platelet count weekly during titration; target <600,000/µL. Avoid in patients with severe hepatic impairment (Child-Pugh C). Use with caution in cardiac disease due to risk of QT prolongation and arrhythmias. Anagrelide may increase bleeding risk, especially when combined with anticoagulants or NSAIDs. Discontinue 4-5 days before elective surgery.
Take folic acid supplements as prescribed to reduce side effects unless on high-dose therapy with leucovorin rescue.,Avoid alcohol completely during treatment due to increased risk of liver damage.,Report any signs of infection, unusual bleeding, or shortness of breath immediately.,Drink plenty of fluids to help flush the drug from your kidneys unless otherwise instructed.,Do not take any over-the-counter medications, especially NSAIDs (like ibuprofen), without consulting your doctor.,Use effective contraception during and for at least 3 months after treatment for both men and women.,Follow your dosing schedule exactly; missed doses can reduce effectiveness or increase toxicity.
Take exactly as prescribed; do not skip doses or double up.,Report any signs of bleeding (easy bruising, nosebleeds, black/tarry stools) or palpitations immediately.,Avoid NSAIDs like ibuprofen and aspirin unless directed by your doctor.,Do not consume grapefruit or grapefruit juice while taking this medication.,Inform all healthcare providers (including dentists) that you are on anagrelide.,Store at room temperature away from moisture and heat.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about FOLEX vs AGRYLIN, answered by our medical review team.
FOLEX is a Antineoplastic Agent that works by Methotrexate, the active ingredient in FOLEX, is a folate analog that inhibits dihydrofolate reductase (DHFR), blocking the conversion of dihydrofolate to tetrahydrofolate, thereby interfering with thymidylate and purine synthesis, leading to inhibition of DNA replication and cell proliferation.. AGRYLIN is a Antineoplastic Agent that works by Agrylin (anagrelide) inhibits cyclic nucleotide phosphodiesterase III (PDE3) and reduces platelet production by interfering with megakaryocyte maturation and proliferation, likely via inhibition of cyclic AMP phosphodiesterase and modulation of intracellular calcium levels.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between FOLEX and AGRYLIN depend on the specific clinical indication. These are both Antineoplastic Agent agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of FOLEX is: 30 mg/m2 intravenously once weekly for 2 weeks followed by a 1-week rest period, or 5-10 mg/m2 intramuscularly or intravenously every 3-4 weeks. For rheumatoid arthritis, 7.5-15 mg orally once weekly.. The standard adult dose of AGRYLIN is: Adults: 0.5 mg orally once or twice daily, increased by 0.5 mg every 2 weeks to maintain platelet count <600,000/µL. Maximum dose: 10 mg/day.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between FOLEX and AGRYLIN in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. FOLEX is classified as Category C. FDA Pregnancy Category X. First trimester: High risk of miscarriage, neural tube defects, craniofacial anomalies, and limb defects. Second and third trimesters: Fetal growth restri. AGRYLIN is classified as Category C. Pregnancy Category C. Anagrelide is not recommended in pregnancy. Animal studies have shown embryotoxicity and teratogenicity (e.g., increased fetal resorptions, skeletal anomalies. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.