busulfan (Myleran)

Introduction

Tradename: Myleran.

Indications

• chronic myelogenous leukemia
• polycythemia vera
• bone marrow ablation prior to bone marrow transplant (stem cell transplantation)*

* major, if not exclusive, use in 2015

Contraindications

Caution:

• monitor for signs of bleeding
• excellent oral hygiene is needed to minimize oral discomfort

Dosage

• adults 408 mg PO QD
• maintenance dosage: 2-4 mg/week to 4 mg QD
• bone marrow transplant: up to 8-16 mg/kg

Tabs: 2 mg.

Pharmacokinetics

well absorbed orally

elimination via liver

1/2life = 2.5 hours

Adverse effects

• common (> 10%)
  • pancytopenia
  • delayed effect, onset 7-10 days
  • nadir 14-21 days
  • recovery 28 days
  • busulfan affects stem cells
• less common (1-10%)
  • amenorrhea, hyperpigmentation, nausea/vomiting, diarrhea, weakness, anorexia, weight loss
• uncommon (< 1%)
  • seizures, adrenal suppression (Addison-like syndrome), hepatic dysfunction, blurred vision, pulmonary fibrosis, hemorrhagic cystitis, gynecomastia, hyperuricemia,
• other
  • mucositis
  • increased serum transaminases
  • "Bulsulfan" lung (< 8%)
    • fever/chills, rales, dyspnea
    • 30 days to 1 year after exposure
    • pulmonary fibrosis, pulmonary nodules, dependent consoligation
    • treatment is generally supportive
    • glucocorticoids may be of benefit

• drug adverse effects of alkylating agents

Drug interactions

• thioguanine
• in combination with probenecid results in increased serum & urine uric acid

Test interactions

• may increase measurements of serum K+

Mechanism of action

alkylating agent

More general terms

• alkylating agent

Database

• PubChem: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=2478