Sickle Cell Anemia and Hydroxyurea

In sickle cell anemia, currently, the best medication we have to prevent complications is called hydroxyurea, sometimes abbreviated HU. Hydroxyurea was first developed as a chemotherapy medication in the 1960s. It was used for a wide variety of malignant conditions initially, but it has been used in sickle cell disease now for more than 25 years. Hydroxyurea was the first medication approved by the FDA (Food and Drug Administration) to treat sickle cell anemia.

The doctor told the details and drug treatment for inpatient treatment.
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How Does Hydroxyurea Work in Sickle Cell Anemia?

In sickle cell anemia, hydroxyurea helps the body produce more fetal hemoglobin (Hb F). This is a hemoglobin found in newborn babies. Newborn babies with sickle cell disease do not have complications in the first few months of life, because fetal hemoglobin prevents the red blood cell from sickling. This increase in fetal hemoglobin helps keep red blood cells round instead of sickled. These round red blood cells are able to flow through blood vessels smoothly.

The Benefits of Hydroxyurea Therapy

In numerous studies in both children and adults with sickle cell anemia, hydroxyurea treatment has been associated with fewer adverse events, reduced acute chest syndrome (lung complications), reduction in the need for transfusion, and reduction in the need for hospitalization. Hydroxyurea also increases hemoglobin, making you less anemic. In addition, hydroxyurea therapy has been associated with longer life expectancy in adults.

Side Effects

Based on the doses used in sickle cell anemia, the side effects of hydroxyurea therapy are relatively mild. Hair loss, mouth sores, and increased risk of infection associated with chemotherapy are rarely seen. Hydroxyurea can decrease white blood cells, hemoglobin, and platelets. Because of this side effect, your physician will monitor your condition closely with complete blood count and reticulocyte count testing. Occasionally, abdominal pain is seen, but this is usually mild and resolves without intervention. Another side effect is darkening of the nails, called melanonychia. However, most patients are able to find a dose of hydroxyurea they can tolerate with few side effects.

What Patients Should Consider Treatment With Hydroxyurea?

According to the most recent sickle cell management guidelines from the National Heart, Lung, and Blood Institute (part of the National Institutes of Health), published in 2014, all children with hemoglobin SS and sickle beta zero thalassemia should be offered hydroxyurea therapy to prevent complications after 9 months of age. In adults, hydroxyurea therapy should be considered for patients who have three or more painful crises per year, pain that interferes with daily activities, a history of acute chest syndrome, or severe anemia that interferes with daily activities.

Does Hydroxyurea Cause Cancer?

Historically, this has been a huge concern. Patients initially treated with hydroxyurea had conditions that increased their risk of malignancy (cancer), and because they developed cancer while on hydroxurea therapy, it was attributed to the medication. However, this supposition has since been proved false. According to a study published in 2014 looking specifically at patients with sickle cell disease, those who took hydroxyurea were not at increased risk of cancer compared to those who did not take hydroxyurea.

Can I Take Hydroxyurea During Pregnancy?

At this time, taking hydroxyurea during pregnancy is not recommended. Hydroxyurea is a class D medication, indicating there appears to be a risk to a developing fetus. There are a small number of cases reporting normal pregnancies in women with sickle cell disease who continued to take hydroxyurea, but additional information is needed.

Can I Ever Stop Taking Hydroxyurea?

No, hydroxyurea is not a cure. It only works if you take it as directed. Hydroxyurea is a chronic medication for a chronic disease similar to medications people with high blood pressure take every day.

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