Take this medicine only as directed by your doctor. Do not take more or less of it, and do not take it more often than your doctor ordered. The exact amount of medicine you need has been carefully worked out. Taking too much may increase the chance of side effects, while taking too little may not improve your condition.
Cyclophosphamide is sometimes given together with certain other medicines. If you are using a combination of medicines, make sure that you take each one at the proper time and do not mix them. Ask your doctor to help you plan a way to remember to take your medicines at the right times.
While you are using cyclophosphamide, it is important that you drink extra fluids so that you will pass more urine. Also, empty your bladder frequently, including at least once during the night. This will help prevent kidney and bladder problems and keep your kidneys working well. Cyclophosphamide passes from the body in the urine. If too much of it appears in the urine or if the urine stays in the bladder too long, it can cause dangerous irritation. Follow your doctor's instructions carefully about how much fluid to drink every day. Some patients may have to drink up to 7 to 12 cups (3 quarts) of fluid a day.
Usually it is best to take cyclophosphamide first thing in the morning, to reduce the risk of bladder problems. However, your doctor may want you to take it with food in smaller doses over the day, to lessen stomach upset or help the medicine work better. Follow your doctor's instructions carefully about when to take cyclophosphamide.
Cyclophosphamide often causes nausea, vomiting, and loss of appetite. However, it is very important that you continue to use the medicine even if you begin to feel ill. Do not stop taking this medicine without first checking with your doctor. Ask your doctor for ways to lessen these effects.
If you vomit shortly after taking a dose of cyclophosphamide, check with your doctor. You will be told whether to take the dose again or to wait until the next scheduled dose.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
For oral dosage form (tablets):
For the treatment of cancer:
Adults—Dose is based on body weight and must be determined by your doctor. The usual dose is 1 to 5 milligrams (mg) per kilogram (kg) of body weight per day.
Children—Dose is based on body weight and must be determined by your doctor. The usual dose is 1 to 5 mg per kg of body weight per day.
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.