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.

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly and to check for unwanted effects.

While you are being treated with cyclophosphamide, and after you stop treatment with it, do not have any immunizations (vaccinations) without your doctor's approval. Cyclophosphamide may lower your body's resistance and there is a chance you might get the infection the immunization is meant to prevent. In addition, other persons living in your house should not take oral polio vaccine since there is a chance they could pass the polio virus on to you. Also, avoid persons who have recently taken oral polio vaccine within the last several months. Do not get close to them, and do not stay in the same room with them for very long. If you cannot take these precautions, you should consider wearing a protective face mask that covers the nose and mouth.

Before having any kind of surgery, including dental surgery, or emergency treatment, make sure the medical doctor or dentist in charge knows that you are taking this medicine, especially if you have taken it within the last 10 days.

Cyclophosphamide can temporarily lower the number of white blood cells in your blood, increasing the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:
If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
Check with your doctor immediately if you notice any unusual bleeding or bruising; black, tarry stools; blood in urine or stools; or pinpoint red spots on your skin.
Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
Avoid contact sports or other situations where bruising or injury could occur.

Before you have any medical tests, tell the medical doctor in charge that you are taking this medicine. The results of some tests may be affected by this medicine.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common: cough or hoarseness, fever or chills, lower back or side pain, missing menstrual periods, painful or difficult urination.

With high doses and/or long-term treatment: blood in urine, dizziness, confusion, or agitation, fast heartbeat, joint pain, shortness of breath, swelling of feet or lower legs, unusual tiredness or weakness.

Less common: black, tarry stools or blood in stools, pinpoint red spots on skin, unusual bleeding or bruising.

Rare: frequent urination, redness, swelling, or pain at site of injection, sores in mouth and on lips, sudden shortness of breath, unusual thirst, yellow eyes or skin.

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common: darkening of skin and fingernails, loss of appetite, nausea or vomiting.

Less common: diarrhea or stomach pain, flushing or redness of face, headache, increased sweating, skin rash, hives, or itching, swollen lips.

Cyclophosphamide may cause a temporary loss of hair in some people. After treatment has ended, normal hair growth should return, although the new hair may be a slightly different color or texture.

After you stop using this medicine, it may still produce some side effects that need attention. During this period of time, check with your doctor immediately if you notice the following side effects:
Blood in urine

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects.