Generic name: cyclophosphamide (oral route, intravenous route) [ sye-kloe-FOS-fa-mide ]
Drug class: Alkylating agents
Medically reviewed by Drugs.com. Last updated on Nov 13, 2022.
The Cytoxan brand name has been discontinued in the U.S. If generic versions of this product have been approved by the FDA, there may be generic equivalents available.
Commonly used brand name(s)
In the U.S.
- Cytoxan Lyophilized
Available Dosage Forms:
- Powder for Solution
Therapeutic Class: Antineoplastic Agent
Pharmacologic Class: Alkylating Agent
Chemical Class: Nitrogen Mustard
Uses for Cytoxan
Cyclophosphamide is used to treat cancer of the ovaries, breast, blood and lymph system, and nerves (mainly in children). Cyclophosphamide is also used for retinoblastoma (a type of eye cancer mainly in children), multiple myeloma (cancer in the bone marrow), and mycosis fungoides (tumors on the skin). It belongs to the group of cancer medicines called alkylating agents.
Cyclophosphamide is also used for some kinds of kidney disease.
Cyclophosphamide interferes with the growth of cancer cells, which are then destroyed by the body. Since the growth of normal body cells may also be affected by cyclophosphamide, other effects will also occur. Some of these may be serious and must be reported to your doctor. Other effects, like hair loss, may not be serious but may cause concern. Some effects may not occur for months or years after the medicine is used.
Before you begin treatment with cyclophosphamide, you and your doctor should talk about the benefits of this medicine as well as the risks of using it.
This medicine is available only with your doctor's prescription.
Before using Cytoxan
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
This medicine has been tested in children and has not been shown to cause different side effects or problems than it does in adults.
Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. Although there is no specific information comparing use of cyclophosphamide in the elderly with use in other age groups, it is not expected to cause different side effects or problems in older people than it does in younger adults.
Studies in women breastfeeding have demonstrated harmful infant effects. An alternative to this medication should be prescribed or you should stop breastfeeding while using this medicine.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Measles Virus Vaccine, Live
- Mumps Virus Vaccine, Live
- Rotavirus Vaccine, Live
- Rubella Virus Vaccine, Live
- Varicella Virus Vaccine, Live
- Zoster Vaccine, Live
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Adenovirus Vaccine
- Bacillus of Calmette and Guerin Vaccine, Live
- Cholera Vaccine, Live
- Dengue Tetravalent Vaccine, Live
- Doxorubicin Hydrochloride Liposome
- Eslicarbazepine Acetate
- Influenza Virus Vaccine, Live
- Poliovirus Vaccine, Live
- Smallpox Vaccine
- St John's Wort
- Typhoid Vaccine, Live
- Yellow Fever Vaccine
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Chickenpox (including recent exposure) or
- Herpes zoster (shingles)—Risk of severe disease affecting other parts of the body.
- Gout, history of or
- Kidney stones, history of—Cyclophosphamide may increase levels of uric acid in the body, which can cause gout or kidney stones.
- Infection—May decrease body's ability to fight infection.
- Kidney disease—The effects of cyclophosphamide may be increased because of slower removal from the body.
- Liver disease—The effect of cyclophosphamide may be decreased.
- Prior removal of adrenal gland(s)—Toxic effects of cyclophosphamide may be increased, dosage adjustment may be necessary.
- Tumor cell accumulation—Increased risk of tumor cells entering the bone marrow, due to bone marrow depression from high doses of cyclophosphamide.
Proper use of Cytoxan
This section provides information on the proper use of a number of products that contain cyclophosphamide. It may not be specific to Cytoxan. Please read with care.
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.
- For the treatment of cancer:
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.
Precautions while using Cytoxan
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 (vaccines) without your doctor's approval. Cyclophosphamide may lower your body's resistance and the vaccine may not work as well or you might get the infection the vaccine is meant to prevent. In addition, you should not be around other persons living in your household who receive live virus vaccines because there is a chance they could pass the virus on to you. Some examples of live vaccines include measles, mumps, influenza (nasal flu vaccine), poliovirus (oral form), rotavirus, and rubella. Do not get close to them and do not stay in the same room with them for very long. If you have questions about this, talk to your doctor.
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 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.
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 the 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.
Cytoxan side effects
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:
- 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 the urine
- dizziness, confusion, or agitation
- fast heartbeat
- joint pain
- shortness of breath
- swelling of the feet or lower legs
- unusual tiredness or weakness
- Black, tarry stools
- pinpoint red spots on the skin
- unusual bleeding or bruising
- Frequent urination
- redness, swelling, or pain at the injection site
- sores in the mouth and on the 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:
- Darkening of the skin and fingernails
- loss of appetite
- nausea or vomiting
- flushing or redness of the face
- increased sweating
- skin rash, hives, or itching
- stomach pain
- swollen lips
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. You may report side effects to the FDA at 1-800-FDA-1088.
Frequently asked questions
More about Cytoxan (cyclophosphamide)
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- During pregnancy
- Drug class: alkylating agents
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