Cytotoxic drugs are very powerful medicines. They work by affecting the growth and action of some cells that cause the joint pain, swelling, warmth, and damage of arthritis. Since Cytotoxic drugs work over a long period of time, you may not notice much effect from the drugs for the first several weeks or months of treatment.

The three cytotoxic drugs usually used to treat arthritis and related conditions are:

Azathioprine (Imuran)

Cyclophosphamide (Cytoxan)

Methotrexate (Rheumatrex)

These drugs are usually given in pill form, but some may be given intravenously or by injection.

Since cytotoxic drugs are very potent and may have serious side effects, doctors prescribe them only when the arthritis is severe and other simpler or safer drugs have failed to bring relief.

Cytotoxic drugs can be used to treat many forms of arthritis, including juvenile rheumatoid arthritis, psoriatic arthritis, rheumatoid arthritis and systemic lupus erythematosus, as well as conditions such as steroid-resistant polymyositis or dermatomyositis, Wegener's granulomatosis, polyarteritis or some forms of vasculitis.

If cytotoxic drugs are recommended for you, be sure to consult a doctor who has experience using these drugs. When considering treatment with cytotoxic drugs, you, your doctor, and your family will want to consider factors such as the severity of your disease, the potential benefits of the drug as well as the potential side effects.

As with other drugs, there are no guarantees that cytotoxic drugs will work for you. For severe medical conditions, many experts agree that, when properly used, the risk of side effects from the drugs may be less than the risk to your health from the disease itself. Talk to your doctor about the side effects and whether the benefits of the medicine outweigh the risks.

What Are The Side Effects?

Cytotoxic drugs cause different side effects in different people. One of the most serious side effects is the suppression of certain cells:

* White blood cells, which help your body fight infections. When these are suppressed, you may get infections more easily.

* Platelets, which help your blood clot. When these are suppressed, you may bruise and/or bleed more easily.

* Red blood cells, which carry oxygen to your tissues. When these are suppressed, you may have anemia (extreme tiredness and fatigue).

Contact your doctor right away if you notice these side effects:

Signs of infection: fever, chills, or very sore throat

Signs of bleeding: any unusual bleeding or bruising, black, tarry stools, a sign of internal bleeding, pinhead-size red spots on lower legs

Signs of anemia: unusual tiredness or weakness

Lung problems caused by methotrexate: cough or severe shortness of breath without a fever

Bladder problems caused by Cytoxan: blood in the urine or painful urination

While these side effects don't happen very often, you should still be aware of them. Some of them are signs of serious problems which should be treated right away.

Other side effects may occur with these drugs. If you have any of these side effects, or other problems not listed here, check with your doctor or pharmacist:

* loss of appetite

* nausea or stomach pain

* diarrhea

* sores or ulcers in the mouth

* hair loss

* missed menstrual periods

* rash

Some cytotoxic drugs may also cause sterility, birth defects, liver damage and possibly certain types of cancer, such as leukemia, lymphoma, or skin or bladder cancer. Ask your doctor to explain the potential risks of these side effects.

What You Can Do About Some Side Effects

The most important thing you can do to treat and help avoid some side effects is to have regular checkups. Here are some other things you can do to handle the following side effects:

Risk for infection: Stay away from adults and children who have contagious illnesses, such as colds, the flu, or chickenpox. Do NOT have any immunizations without checking with your doctor, because they could lead to infection. Report any sign of an infection to your doctor, right away.

Loss of appetite: Plan meals when you're not feeling nauseous. Try eating small, more frequent meals. Ask your doctor if you can take the medicine at bedtime to reduce this side effect.

Mouth sores: Contact your doctor if these develop. Use a soft-bristled toothbrush. Use salt water or peroxide as a mouth wash. Eat soft, non-spicy foods of medium to cold temperature. If the pain doesn't go away, ask your doctor about using a topical pain reliever before meals.

Easy bruising or bleeding: This could be a sign of serious problems, so you should contact your doctor right away.

What Should I Tell My Doctor Before I Use Cytotoxic Drugs?

Your doctor needs to know about the following conditions in order to decide whether to recommend cytotoxic drugs:

* If you are pregnant or if you plan to have children: cytotoxic drugs may cause birth defects if either parent is taking them during the time of conception, or if taken during pregnancy. These drugs may also cause short- or long-term sterility. After treatment is stopped, women should wait at least one menstrual cycle before trying to get pregnant. Men should wait at least three months before trying to have children.

* If you have allergies to any medications.

* If you are breast-feeding: breast-feeding is generally not recommended while taking these medications.

* If you are taking any other medications, vitamins, mineral supplements or over-the-counter drugs: don't take other medications without your doctor's approval.

* If you have any other medical problems, especially kidney or liver disease.

* If you are often around people who have colds, the flu, or other infections: you may have a higher risk of catching their infection.

* If you have ever been treated with x-rays or cancer medications.

* If you drink alcohol.

What You Should Know About Cytotoxic Drugs

Each cytotoxic drug is different and has its own special instructions.

Azathioprine (Imuran): Usually given in pill form (2-3 tablets daily) or by injection. The dose may be lowered by your doctor after the desired response is obtained.

Special instructions:

* Do not take with allopurinol (Zyloprim) a drug used to treat gout. The combination of these two drugs may be toxic.

* Take the drug with or after meals, to reduce stomach upset.

Cyclophosphamide (Cytoxan): Usually given in pill form or intravenously, according to a prescribed schedule. It is probably the strongest cytotoxic drug. It may cause additional side effects, such as cystitis (inflammation of the bladder marked by blood in the urine and painful urination), as well as bladder cancer.

Special instructions:

* Drink extra fluids every day to help dilute toxic build-up in the bladder. Ask your doctor how much extra fluid to drink.

* Do not take cyclophosphamide at bedtime. It will build up in your urine and will stay in your bladder too long. Some doctors recommend emptying your bladder in the middle of the night at least once, even if it means setting an alarm clock to do so.

Methotrexate (Rheumatrex): Usually given in pill form and sometimes by weekly injections. This drug can cause additional side effects, such as liver scarring (cirrhosis), and a lung problem similar to pneumonia, which causes shortness of breath, cough, and a fever.

Special instructions:

* If you accidentally take too much, contact your doctor right away to receive an antidote.

* Do not drink alcohol while taking this drug, because it can make any liver problems worse.