Hydroxycarbamide Hikma Farmacêutica (Portugal), S.A. (Hydroxycarbamide)

Hydroxycarbamide is used to treat hematologic malignancies and myeloproliferative disorders.

• Chronic myelogenous leukemia: reduces leukemic cell proliferation and disease progression.
• Sickle cell disease: decreases the frequency of painful vaso‑occlusive crises.
• Essential thrombocythemia: lowers elevated platelet counts and reduces thrombotic risk.
• Polycythemia vera: diminishes red blood cell mass and helps control hematocrit levels.
• Melanoma: employed as adjunct therapy to inhibit tumor growth.

• Hydroxycarbamide inhibits ribonucleotide reductase, the enzyme responsible for converting ribonucleotides to deoxyribonucleotides. This blockade reduces the intracellular pool of deoxyribonucleotides, limiting DNA synthesis and cell replication, particularly in rapidly dividing malignant and dysregulated hematopoietic cells.

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

Common Side Effects

• Nausea: mild to moderate upset stomach.
• Vomiting: occasional episodes after dosing.
• Diarrhea: loose stools that may affect hydration.
• Skin rash: erythematous or pruritic lesions.
• Fatigue: generalized tiredness.
• Alopecia: temporary hair loss.

Serious or Rare Side Effects

• Bone marrow suppression: leading to anemia, neutropenia or thrombocytopenia.
• Severe infection: opportunistic infections due to immunosuppression.
• Liver toxicity: elevated transaminases or hepatitis.
• Hypersensitivity reactions: angioedema or anaphylaxis.
• Secondary malignancies: rare development of new cancers.
• Renal failure: impaired kidney function in susceptible patients.

Before initiating Hydroxycarbamide therapy, several safety considerations are recommended.

• Monitor blood counts: regular CBC to detect marrow suppression.
• Assess liver function: periodic LFTs to identify hepatotoxicity.
• Evaluate renal function: baseline and follow‑up creatinine measurements.
• Avoid use in pregnancy unless essential: discuss risks with a specialist.
• Counsel on infection risk: advise patients to report fevers promptly.
• Store at ambient temperature: keep in the original container, protect from moisture and light.

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

Major Interactions (Avoid)

• Concurrent myelosuppressive agents: may exacerbate bone‑marrow toxicity.
• Strong CYP enzyme inhibitors: can increase hydroxycarbamide plasma levels.
• Allopurinol: may potentiate hematologic toxicity.

Moderate Interactions (Monitor Closely)

• NSAIDs: increase risk of gastrointestinal irritation.
• Anticoagulants: may enhance bleeding tendency.
• ACE inhibitors: potential for additive renal effects.
• Live vaccines: reduced vaccine efficacy and increased infection risk.
• Alcohol: may worsen liver toxicity.