Indication |
For palliative treatment in the management malignant neoplasm (trachea, bronchus, lung), squamous cell carcinoma, and lymphomas. |
Pharmacodynamics |
Bleomycin is an antibiotic which has been shown to have
antitumor activity. Bleomycin selectively inhibits the synthesis of
deoxyribonucleic acid (DNA). The guanine and cytosine content correlates
with the degree of mitomycin-induced cross-linking. At high
concentrations of the drug, cellular RNA and protein synthesis are also
suppressed. Bleomycin has been shown in vitro to inhibit B cell, T
cell, and macrophage proliferation and impair antigen presentation, as
well as the secretion of interferon gamma, TNFa, and IL-2. The
antibiotic antitumor drugs are cell cycle-nonspecific except for
Bleomycin (which has major effects in G2 and M phases). |
Mechanism of action |
Although the exact mechanism of action of bleomycin is unknown,
available evidence would seem to indicate that the main mode of action
is the inhibition of DNA synthesis with some evidence of lesser
inhibition of RNA and protein synthesis. DNA cleavage by bleomycin
depends on oxygen and metal ions, at least in vitro. It is believed that
bleomycin chelates metal ions (primarily iron) producing a
pseudoenzyme that reacts with oxygen to produce superoxide and hydroxide
free radicals that cleave DNA. |
Absorption |
Systemic absorption is approximately 45%. |
Volume of distribution |
Not Available |
Protein binding |
1% |
Metabolism |
Hepatic |
Route of elimination |
It was reported that patients with moderately severe renal failure excreted less than 20% of the dose in the urine. |
Half life |
115 minutes |
Clearance |
Not Available |
Toxicity |
Excessive exposure may cause fever, chills, nausea, vomiting,
mental, confusion, and wheezing. Bleomycin may cause irritation to eyes,
skin and respiratory tract. It may also cause a darkening or thickening
of the skin. It may cause an allergic reaction. |