Precautions

It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using this medicine, tell your doctor right away.

Do not use this medicine if you are also using clarithromycin (Biaxin®), itraconazole (Sporanox®), ketoconazole (Nizoral®), nefazodone (Serzone®), nelfinavir (Viracept®), or telithromycin (Ketek®). Using these medicines together may cause serious unwanted effects.

This medicine may increase your risk for heart rhythm problems, including atrial fibrillation and bradycardia. Check with your doctor right away if you have fast, slow, or irregular heartbeat, dizziness, fainting, or trouble breathing while using this medicine.

This medicine may cause temporary visual brightness, usually caused by sudden changes in light (luminous phenomena or phosphenes). This may happen within the first 2 months of treatment with this medicine. Use caution when driving or using machines where sudden changes in light can happen, especially when driving at night.

Do not take other medicines unless thy have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.