e. Hemorrhagic cystitis: Hematuria is not uncommon at this dose 
level, but is usually not symptomatic or severe. Adequate urine 
flow is essential to avoid cystitis. All patients will be treated 
with MESNA coincident with each dose of CTX (see below). 
Pyridium will given for symptomatic relief. 
f. Alopecia: Usually reversible. 
g. Skin rash: Ten to 20% of patients develop a diffuse maculo- 
papular rash 24-72 hours following CTX. The rash usually 
clears in 24-48 hours. 
h. Anemia: Hemoglobin drops can occur at this dose, presumably 
due to hemolysis. 
i. Reproduction: The long term effects are unknown but sterility 
is probable. 
9.3 Mesna (MESNCX) NDC #0015-3561-41 
Mesna is a sulfhydryl compound, 2-mercaptoethane sulfonate which has been 
shown in clinical studies to be effective in preventing CTX induced 
hemorrhagic cystitis. Mesna combines with and inactivates the metabolites of 
CTX which are toxic to the mucosa of the bladder. On entering the plasma, 
Mesna is oxidized to a polar disulfide (dimesna) which does not react with 
Cytoxan metabolites. The kidney then transforms dimesna back to mesna 
which inactivates cytoxan metabolites in the urine. Thus, Mesna does not 
interfere with the antineoplastic and immunosuppressive effects of cytoxan but 
does selectively protect the bladder epithelium from its toxic metabolites. 
9.3.1 Dosage: 
a. Supplied as 400 mg/4 ml vial. 
b. Dissolved in D 5 W to 20 mg/ml concentration. 
c. Mesna 12 mg/kg is delivered IV over 15 minutes prior to CTX 
and 3, 6 , 9, and 12 hours after each dose of cytoxan. 
d. Total 20 doses Mesna (5 for each dose of CTX) will be ad- 
ministered with BU/CTX preparatory regimen. 
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Recombinant DNA Research, Volume 14 
