Drug Interactions between allopurinol and ifosfamide

Allopurinol should generally be taken after a meal to reduce side effects. If your daily dose exceeds 300 mg, you may also ask your healthcare provider if it is okay to divide the total daily dose into smaller doses given more frequently instead of once a day, as this may also reduce stomach upset that can happen with allopurinol. It is best to avoid or limit the consumption of alcohol, as it can increase drowsiness or other nervous system side effects of allopurinol. You should also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Do not consume grapefruit or grapefruit juice while you are receiving treatment with ifosfamide, as this may decrease the anticancer effects of ifosfamide and may increase its adverse effects on your nervous system and your kidneys. Do not use alcohol while you are receiving treatment with ifosfamide. This may increase nervous system side effects such as somnolence, dizziness, confusion, difficulty concentrating, and impairment of thinking and judgment; and may also increase nausea and vomiting. Talk to your doctor or pharmacist if you have questions on how to take this or other medications you are prescribed. Also, avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medication without first talking to your doctor.