Important: This page is general information, not medical advice. It does not recommend or prescribe any treatment. Always consult your doctor or pharmacist before starting, stopping or changing any medicine.
Quick facts
- Drug class
- Antimetabolite [EPC]
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 197797
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Hydroxyurea capsules, USP is indicated for the treatment of: Resistant chronic myeloid leukemia. Locally advanced squamous cell carcinomas of the head and neck (excluding the lip) in combination with chemoradiation. Hydroxyurea capsules, USP is an antimetabolite indicated for the treatment of: • Resistant chronic myeloid leukemia. (1) • Locally advanced squamous cell carcinomas of the head and neck, (excluding lip) in combination with concurrent chemoradiation. (1)
About this medicine
Hydroxyurea Capsules USP is an antimetabolite available for oral use as capsules containing 500 mg hydroxyurea, USP. Inactive ingredients include Colorants (D&C Yellow No. 10, FD&C Red No.3, FD&C Blue No.1), gelatin, lactose anhydrous, magnesium stearate and silicon dioxide and titanium dioxide. Hydroxyurea is a White or almost white, crystalline powder. It is hygroscopic and soluble in water, but practically insoluble in alcohol. The empirical formula is CH 4 N 2 O 2 and it has a molecular weight of 76.05. Its structural formula is: image description
Who should not take it
Hydroxyurea capsules is contraindicated in patients who have demonstrated a previous hypersensitivity to hydroxyurea or any other component of the formulation. • In patients who have demonstrated a previous hypersensitivity to hydroxyurea or any other component of its formulation. (4)
Warnings and cautions
Myelosuppression: Do not give if bone marrow function is markedly depressed. Monitor blood counts at baseline and throughout treatment. Interrupt treatment and reduce dose as necessary. (5.1) Hemolytic anemia: Monitor blood counts throughout treatment. If hemolysis persists, discontinue Hydroxyurea. (5.2) Malignancies: Advise protection from sun exposure and monitor for secondary malignancies. ( 5.3) Embryo-Fetal toxicity: Can cause fetal harm. Advise of potential risk to a fetus and use of effective contraception. ( 5.4 , 8.1 , 8.3 ) Vasculitic toxicities: Discontinue hydroxyurea and initiate treatment if this occurs. (5.5) Live Vaccinations: Avoid live vaccine use in a patient taking hydroxyurea capsules. (5.6) Risks with concomitant use of antiretroviral drugs: Pancreatitis, hepatotoxicity, and neuropathy have occurred. Monitor for signs and symptoms in patients with HIV infection using antiretroviral drugs; discontinue hydroxyurea capsules and implement treatment. (5.7) Radiation recall: Monitor for skin erythema in patients who previously received radiation and manage symptomatically. (5.8) 5.1 Myelosuppression s ion Hydroxyurea causes severe myelosuppression. Treatment with hydroxyurea should not be initiated if bone marrow function is markedly depressed. Bone marrow suppression may occur, and leukopenia is generally its first and most common manifestation. Thrombocytopenia and anemia occur less often and are seldom seen without a preceding leukopenia. Bone marrow depression is more likely in patients who have previously received radiotherapy or cytotoxic cancer chemotherapeutic agents; use hydroxyurea cautiously in such patients. Evaluate hematologic status prior to and during treatment with hydroxyurea capsules. Provide supportive care and modify dose or discontinue hydroxyurea as needed. Recovery from myelosuppression is usually rapid when therapy is interrupted. 5.2 Hemolytic Anemia Cases of hemolytic anemia in patients treated with hydroxyurea for myeloproliferative diseases have been reported [see Adverse Reactions (6.1) ]. […]
Reported side effects
• Myelosuppression [see Warnings and Precautions (5.1) ] • Hemolytic anemia [see Warnings and Precautions (5.2) ] • Malignancies [see Warnings and Precautions (5.3) ] • Vasculitic toxicities [see Warnings and Precautions (5.5) ] • Risks with concomitant use of antiretroviral drugs [see Warnings and Precautions (5.7) ] • Radiation recall [see Warnings and Precautions (5.8) ] • Macrocytosis [see Warnings and Precautions (5.9) ] • Pulmonary Toxicity [see Warnings and Precautions (5.10) ] Most common adverse reactions (≥30%) are hematological, gastrointestinal symptoms, and anorexia. (6) To report SUSPECTED ADVERSE REACTIONS, contact Leading Pharma, LLC at 1-844-740-7500 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Postmarketing Experience The following adverse reactions have been identified during post-approval use of hydroxyurea capsules. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency. Reproductive System and Breast disorders: azoospermia, and oligospermia Gastrointestinal disorders: stomatitis, nausea, vomiting, diarrhea, and constipation Metabolism and Nutrition disorders: anorexia, tumor lysis syndrome Skin and subcutaneous tissue disorders: maculopapular rash, skin ulceration, cutaneous lupus erythematosus, dermatomyositis-like skin changes, peripheral and facial erythema, hyperpigmentation, nail hyperpigmentation, atrophy of skin and nails, scaling, violet papules, and alopecia Renal and urinary disorders: dysuria, elevations in serum uric acid, blood urea nitrogen (BUN), and creatinine levels Nervous system disorders: headache, dizziness, drowsiness, disorientation, hallucinations, and convulsions General Disorders: fever, chills, malaise, edema, and asthenia Hepatobiliary disorders: elevation of hepatic enzymes, cholestasis, and hepatitis Respiratory disorders: diffuse pulmonary infiltrates, dyspnea, and pulmonary fibrosis, interstitial lung disease, pneumonitis, alveolitis, allergic alveolitis and cough Immune disorders: systemic lupus erythematosus Hypersensitivity: Drug-induced fever (pyrexia) (>39°C, >102°F) requiring hospitalization has been […]
Interactions with other medicines
Antiretroviral drugs (7.1) Laboratory Test Interference. (7.2) 7.1 Increased Toxicity with Concomitant Use of Antiretroviral Drugs Pancreatitis In patients with HIV infection during therapy with hydroxyurea and didanosine, with or without stavudine, fatal and nonfatal pancreatitis have occurred. Hydroxyurea is not indicated for the treatment of HIV infection; however, if patients with HIV infection are treated with hydroxyurea, and in particular, in combination with didanosine and/or stavudine, close monitoring for signs and symptoms of pancreatitis is recommended. Permanently discontinue therapy with hydroxyurea in patients who develop signs and symptoms of pancreatitis. Hepatotoxicity Hepatotoxicity and hepatic failure resulting in death have been reported during postmarketing surveillance in patients with HIV infection treated with hydroxyurea and other antiretroviral drugs. Fatal hepatic events were reported most often in patients treated with the combination of hydroxyurea, didanosine, and stavudine. Avoid this combination. Peripheral Neuropathy Peripheral neuropathy, which was severe in some cases, has been reported in patients with HIV infection receiving hydroxyurea in combination with antiretroviral drugs, including didanosine, with or without stavudine. 7.2 Laboratory Test Interference Interference with Uric Acid, Urea, or Lactic Acid Assays Studies have shown that there is an analytical interference of hydroxyurea with the enzymes (urease, uricase, and lactate dehydrogenase) used in the determination of urea, uric acid, and lactic acid, rendering falsely elevated results of these in patients treated with hydroxyurea. Interference with Continuous Glucose Monitoring Systems Hydroxyurea may falsely elevate sensor glucose results from certain continuous glucose monitoring (CGM) systems and may lead to hypoglycemia if sensor glucose results are relied upon to dose insulin. If a patient using a CGM is to be prescribed hydroxyurea, consult with the CGM prescriber about alternative glucose monitoring methods. […]
Use in specific groups
Lactation: Advise women not to breastfeed. (8.2) Geriatric Use: Care should be taken in dose selection and may require a lower dose regimen and monitoring of renal function. (8.5) 8.1 Pregnancy Risk Summary Hydroxyurea capsules can cause fetal harm based on findings from animal studies and the drug’s mechanism of action [see Clinical Pharmacology (12.1) ]. There are no data with hydroxyurea capsules use in pregnant women to inform a drug-associated risk. In animal reproduction studies, administration of hydroxyurea to pregnant rats and rabbits during organogenesis produced embryotoxic and teratogenic effects at doses 0.8 times and 0.3 times, respectively, the maximum recommended human daily dose on a mg/m 2 basis (see Data). Advise women of the potential risk to a fetus and to avoid becoming pregnant while being treated with hydroxyurea capsules. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2%–4% and 15%–20%, respectively. Data Animal Data Hydroxyurea has been demonstrated to be a potent teratogen in a wide variety of animal models, including mice, hamsters, cats, miniature swine, dogs, and monkeys at doses within 1-fold of the human dose given on a mg/m 2 basis. Hydroxyurea is embryotoxic and causes fetal malformations (partially ossified cranial bones, absence of eye sockets, hydrocephaly, bipartite sternebrae, missing lumbar vertebrae) at 180 mg/kg/day (about 0.8 times the maximum recommended human daily dose on a mg/m 2 basis) in rats and at 30 mg/kg/day (about 0.3 times the maximum recommended human daily dose on a mg/m 2 basis) in rabbits. Embryotoxicity was characterized by decreased fetal viability, reduced live litter sizes, and developmental delays. Hydroxyurea crosses the placenta. Single doses of ≥375 mg/kg (about 1.7 times the maximum recommended human daily dose on a mg/m 2 basis) to rats caused growth retardation and impaired learning ability. 8.2 Lactation Risk Summary Hydroxyurea is excreted in human milk. […]
If too much is taken
Acute mucocutaneous toxicity has been reported in patients receiving hydroxyurea at dosages several times the therapeutic dose. Soreness, violet erythema, edema on palms and soles followed by scaling of hands and feet, severe generalized hyperpigmentation of the skin, and stomatitis have also been observed.
Before you take anything new
Tell your pharmacist or doctor about every medicine you take — including ones bought without a prescription, herbal products and supplements. Interactions are one of the most common avoidable causes of harm from medicines, and a pharmacist can check your full list in a couple of minutes.
This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 25 November 2024. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.