Jylamvo (Methotrexate)

Methotrexate is used in several disease categories, primarily targeting immune‑mediated disorders and certain cancers.

• Rheumatoid arthritis: reduces joint inflammation and slows disease progression.
• Psoriasis: improves skin lesions and decreases severity of plaque formation.
• Acute lymphoblastic leukemia: interferes with malignant cell proliferation as part of chemotherapy protocols.
• Lymphoma: contributes to tumor control when combined with other agents.
• Ectopic pregnancy: terminates trophoblastic tissue to avoid surgical intervention.

• Methotrexate acts as a folate antagonist by competitively inhibiting the enzyme dihydrofolate reductase. This inhibition blocks the conversion of dihydrofolate to tetrahydrofolate, a cofactor required for synthesis of purine nucleotides and thymidylate. Consequently, DNA, RNA and protein synthesis are reduced, leading to decreased proliferation of rapidly dividing cells and modulation of immune cell activity. It also influences cytokine production and promotes apoptosis of activated T cells.

Methotrexate may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Nausea: mild to moderate stomach upset that may be accompanied by loss of appetite.
• Fatigue: persistent sense of tiredness that can affect daily activities.
• Elevated liver enzymes: mild hepatic irritation reflected in increased ALT/AST levels on routine labs.

Serious or Rare Side Effects

• Severe liver toxicity: potential for hepatitis, fibrosis, or cirrhosis requiring regular monitoring.
• Pulmonary fibrosis: interstitial lung disease presenting with cough, shortness of breath, and reduced lung capacity.
• Bone marrow suppression: severe pancytopenia leading to increased risk of infection, anemia, and bleeding.

When prescribing methotrexate, several safety measures and monitoring steps are recommended.

• Baseline labs: obtain liver function tests, renal function and complete blood count before initiation.
• Pregnancy avoidance: contraindicated in pregnancy; effective contraception required for women of childbearing potential.
• Renal function: adjust use or avoid in patients with impaired kidney function.
• Hepatic monitoring: perform regular liver enzyme assessments during therapy.
• Infection risk: monitor for signs of infection and advise patients to report fevers promptly.
• Store at ambient temperature: keep tablets in original container, protect from moisture and heat.

Methotrexate has a notable interaction profile that requires careful review of concomitant medications.

Major Interactions (Avoid)

• Non‑steroidal anti‑inflammatory drugs (NSAIDs): can increase methotrexate toxicity by reducing renal clearance.
• Proton pump inhibitors (e.g., omeprazole): may elevate methotrexate plasma levels.
• Trimethoprim‑sulfamethoxazole: potentiates bone marrow suppression.

Moderate Interactions (Monitor Closely)

• Live vaccines: risk of infection due to immunosuppression.
• Azathioprine or other immunosuppressants: additive myelosuppression.
• Alcohol: may exacerbate hepatic toxicity.
• Penicillins: can reduce renal excretion of methotrexate.