HYDREA- hydroxyurea capsule
E.R. Squibb & Sons, L.L.C.
1 INDICATIONS AND USAGE
HYDREA is indicated for the treatment of:
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Resistant chronic myeloid leukemia.
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Locally advanced squamous cell carcinomas of the head and neck (excluding the lip) in combination with chemoradiation.
2 DOSAGE AND ADMINISTRATION
2.1 Dosing Information
?HYDREA is used alone or in conjunction with other antitumor agents or radiation therapy to treat neoplastic diseases. Individualize treatment based on tumor type, disease state, response to treatment, patient risk factors, and current clinical practice standards.
Base all dosage on the patient�s actual or ideal weight, whichever is less.
HYDREA is a cytotoxic drug. Follow applicable special handling and disposal procedures [see References (15)].
Prophylactic administration of folic acid is recommended [see Warnings and Precautions (5.7)].
2.2 Dose Modifications for Toxicity
? Monitor for the following and reduce the dose or discontinue HYDREA accordingly:
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Myelosuppression [see Warnings and Precautions (5.1)]
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Cutaneous vasculitis [see Warnings and Precautions (5.4)]
?Monitor blood counts at least once a week during HYDREA therapy. Severe anemia must be corrected before initiating therapy with HYDREA. Consider dose modifications for other toxicities.
DESCRIPTION
HYDREA (hydroxyurea capsules, USP) is an antimetabolite available for oral use as capsules containing 500 mg hydroxyurea. Inactive ingredients include citric acid, colorants (D&C Yellow No. 10, FD&C Blue No. 1, FD&C Red No. 40, and D&C Red No. 28), gelatin, lactose, magnesium stearate, sodium phosphate, and titanium dioxide.
Hydroxyurea is a white to off-white crystalline powder. It is hygroscopic and freely soluble in water, but practically insoluble in alcohol. The empirical formula is CH4 N2 O2 and it has a molecular weight of 76.05. Its structural formula is:
Hydroxyurea Chemical StructureHydroxyurea Chemical Structure
12 CLINICAL PHARMACOLOGY
12.1 Mechanism of Action
The precise mechanism by which hydroxyurea produces its antineoplastic effects cannot, at present, be described. However, the reports of various studies in tissue culture in rats and humans lend support to the hypothesis that hydroxyurea causes an immediate inhibition of DNA synthesis by acting as a ribonucleotide reductase inhibitor, without interfering with the synthesis of ribonucleic acid or of protein. This hypothesis explains why, under certain conditions, hydroxyurea may induce teratogenic effects
