It is very important that your doctor check your or your child's progress at regular visits to make sure this medicine is working properly. Blood and urine tests may be needed to check for unwanted effects.
If your or your child's symptoms do not improve, or if they become worse, check with your doctor. Continue to take this medicine as directed.
You or your child should not use astemizole (Hismanal®), cisapride (Propulsid®), erythromycin (Ery-Tab®), pimozide (Orap®), quinidine (Cardioquin®), or terfenadine (Seldane®) while using this medicine because of the risk of unwanted side effects.
Using this medicine for a long time or using it too much while you are pregnant (especially during the first trimester) can harm your unborn baby. Use an effective form of birth control during treatment with this medicine and for at least 1 week after the last dose. If you think you have become pregnant while using this medicine, tell your doctor right away.
This medicine may rarely cause serious liver problems. Check with your doctor right away if you or your child are having more than one of these symptoms: abdominal or stomach pain or tenderness, clay-colored stools, dark urine, decreased appetite, fever, headache, itching, loss of appetite, nausea and vomiting, skin rash, swelling of the feet or lower legs, unusual tiredness or weakness, or yellow eyes or skin.
This medicine may rarely cause a serious type of allergic reaction called anaphylaxis, which can be life-threatening and requires immediate medical attention. Call your doctor right away if you or your child have a rash, itching, hives, hoarseness, trouble with breathing, trouble with swallowing, or any swelling of your hands, face, or mouth while you are using this medicine.
Serious skin reactions can occur in certain people during treatment with this medicine. Check with your doctor right away if you or your child start having a skin rash, itching, or any other skin changes while using this medicine.
Contact your doctor right away if you have any changes to your heart rhythm. You might feel dizzy or faint, or you might have a fast, pounding, or uneven heartbeat. Make sure your doctor knows if you or anyone in your family has ever had a heart rhythm problem such as QT prolongation.
This medicine may cause adrenal gland problems. Check with your doctor right away if you have darkening of the skin, diarrhea, dizziness, fainting, loss of appetite, mental depression, nausea, skin rash, unusual tiredness or weakness, or vomiting.
This medicine may cause some people to become dizzy, drowsy, or less alert than they are normally. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.