Hydroxycarbamid Sandoz (Hydroxycarbamide)

Hydroxycarbamide is employed in hematologic conditions that involve abnormal blood cell production or sickling of red cells.

• Sickle cell disease: reduces frequency of painful crises and the need for blood transfusions.
• Polycythemia vera: helps control elevated red blood cell mass and lowers thrombotic risk.
• Essential thrombocythemia: decreases platelet counts and mitigates clotting complications.
• Chronic myelogenous leukemia: used as part of combination therapy to limit disease progression.

• Hydroxycarbamide inhibits ribonucleotide reductase, the enzyme responsible for converting ribonucleotides to deoxyribonucleotides. This blockade reduces the pool of deoxyribonucleotides required for DNA synthesis, leading to decreased proliferation of rapidly dividing cells, including malignant hematopoietic clones and sickled erythrocytes. The resulting cytoreduction and fetal hemoglobin induction underlie its therapeutic effects in myeloproliferative disorders and sickle cell disease.

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

Common Side Effects

• Nausea or vomiting.
• Mild skin rash or itching.
• Transient low white blood cell counts.
• Mild anemia or fatigue.
• Mouth ulcers or sore throat.
• Mild elevation of liver enzymes.

Serious or Rare Side Effects

• Severe neutropenia leading to infection risk.
• Significant thrombocytopenia causing bleeding.
• Acute renal impairment.
• Pulmonary toxicity or fibrosis.
• Rare hypersensitivity reactions such as Stevens‑Johnson syndrome.
• Potential teratogenic effects in pregnancy.

Before initiating therapy, clinicians should evaluate patient history and monitor laboratory parameters.

• Baseline blood counts: obtain complete blood count to assess marrow reserve.
• Renal function: evaluate serum creatinine and adjust if impairment is present.
• Hepatic function: monitor liver enzymes for potential toxicity.
• Pregnancy status: avoid use in pregnant women due to unknown safety.
• Concomitant myelosuppressive drugs: assess risk of additive bone‑marrow suppression.
• Store at ambient temperature: keep below 25 °C, in the original packaging, protected from moisture and direct sunlight.

Hydroxycarbamide can interact with other medicines, altering efficacy or safety.

Major Interactions (Avoid)

• Concurrent use with other strong myelosuppressants (e.g., azathioprine) may cause profound bone‑marrow suppression.
• Live vaccines: increased risk of infection; avoid administration during treatment.

Moderate Interactions (Monitor Closely)

• Allopurinol: may increase hydroxycarbamide plasma levels; monitor blood counts.
• NSAIDs: can exacerbate renal toxicity; assess renal function regularly.
• Antiretroviral agents (e.g., zidovudine): potential additive hematologic toxicity.
• Phenytoin: may reduce hydroxycarbamide effectiveness; consider dose adjustment.
• Vitamin C high doses: may increase drug absorption; monitor for toxicity.