What Is It?: Hydroxyurea is an antineoplastic (drug that prevents, kills or blocks the growth or spread of cancer cells) used for the treatment of polycythemia vera, mastocytomas, and leukemias in dogs and cats.

How To Use: Dogs and cats usually receive this medicine by mouth once to twice daily. It is commonly supplied in a capsule form.

Possible Side Effects: Side effects from hydroxyurea are common and include: nausea and vomiting, loss of appetite, constipation, diarrhea. Tell your doctor if either of these symptoms is severe or lasts for several hours: fatigue or drowsiness, mouth blistering. If you experience any of the following symptoms, call your doctor immediately: unusual bruising or bleeding, persistent diarrhea or any change in normal bowel habits for more than 2 days, fever, chills, sore throat, rash, itching, tingling of the hands and feet, yellowing of the skin or eyes, pain in the right upper part of the stomach.

Storage: Keep in the original container. Keep out of the reach of children and pets. Capsules and tablets may be stored at room temperature. Some liquids should be stored in the refrigerator (see the prescription label.)  Store all medicines away from excess heat and moisture. Do NOT store in the bathroom.

Note: If you miss a dose give it as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue with the regular schedule. Do not give a double dose to make up for the missed one.