In the U.S.—

In Canada—

• Antineoplastic

Estramustine ( ess-tra-MUSS-teen) belongs to the general group of medicines called antineoplastics. It is used to treat some cases of prostate cancer.

Estramustine is a combination of two medicines, an estrogen and mechlorethamine. The way that estramustine works against cancer is not completely understood. However, it seems to interfere with the growth of cancer cells, which are eventually destroyed.

Estramustine is available only with your doctor's prescription, in the following dosage form:

Oral
• Capsules (U.S. and Canada)

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 estramustine, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to estramustine, estrogens, or mechlorethamine.

Pregnancy—There is a chance that this medicine may cause birth defects if the male is taking it at the time of conception. It may also cause permanent sterility after it has been taken for a while. Be sure that you have discussed this with your doctor before taking this medicine. Before taking estramustine, make sure your doctor knows if you intend to have children.

Older 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 or if they cause different side effects or problems in older people. There is no specific information comparing use of estramustine in the elderly with use in other age groups.

Other 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 estramustine, it is especially important that your health care professional know if you are taking any of the following:

• Acetaminophen (e.g., Tylenol) (with long-term, high-dose use) or
• Amiodarone (e.g., Cordarone) or
• Anabolic steroids (nandrolone [e.g., Anabolin], oxandrolone [e.g., Anavar], oxymetholone [e.g., Anadrol], stanozolol [e.g., Winstrol]) or
• Androgens (male hormones) or
• Anti-infectives by mouth or by injection (medicine for infection) or
• Antithyroid agents (medicine for overactive thyroid) or
• Carbamazepine (e.g., Tegretol) or
• Carmustine (e.g., BiCNU) or
• Chloroquine (e.g., Aralen) or
• Dantrolene (e.g., Dantrium) or
• Disulfiram (e.g., Antabuse) or
• Divalproex (e.g., Depakote) or
• Estrogens (female hormones) or
• Etretinate (e.g., Tegison) or
• Gold salts (medicine for arthritis) or
• Hydroxychloroquine (e.g., Plaquenil) or
• Mercaptopurine (e.g., Purinethol) or
• Methotrexate (e.g., Mexate) or
• Methyldopa (e.g., Aldomet) or
• Naltrexone (e.g., Trexan) (with long-term, high-dose use) or
• Oral contraceptives (birth control pills) containing estrogen or
• Phenothiazines (acetophenazine [e.g., Tindal], chlorpromazine [e.g., Thorazine], fluphenazine [e.g., Prolixin], mesoridazine [e.g., Serentil], perphenazine [e.g., Trilafon], prochlorperazine [e.g., Compazine], promazine [e.g., Sparine], promethazine [e.g., Phenergan], thioridazine [e.g., Mellaril], trifluoperazine [e.g., Stelazine], triflupromazine [e.g., Vesprin], trimeprazine [e.g., Temaril]) or
• Phenytoin (e.g., Dilantin) or
• Plicamycin (e.g., Mithracin) or
• Valproic acid (e.g., Depakene)—May increase the risk of liver problems

• Tobacco, smoking—Smoking causes narrowing of blood vessels and may increase the risk of serious circulation problems, which can lead to stroke or heart attack

• Asthma or
• Epilepsy or
• Mental depression (or history of) or
• Migraine headaches or
• Kidney disease—Fluid retention sometimes caused by estramustine may worsen these conditions

• Blood clots (or history of) or
• Stroke (or history of) or
• Recent heart attack or stroke—May be worsened because of blood vessel problems caused by estramustine

• Chickenpox (including recent exposure) or
• Herpes zoster (shingles)—Risk of severe disease affecting other parts of the body

• Diabetes mellitus (sugar diabetes)—Estramustine may change the amount of antidiabetic medicine needed

• Gallbladder disease (or history of)—May be worsened by estramustine

• Heart or blood vessel disease—Estramustine can cause circulation problems

• Jaundice or hepatitis (or history of) or other liver disease—Effects, including liver problems, may be increased

• Stomach ulcer—May be aggravated by estramustine

Use this medicine only as directed by your doctor. Do not use more or less of it, and do not use 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.

Do not take estramustine within 1 hour before or 2 hours after meals or after the time you take milk, milk formulas, or other dairy products, since they may keep the medicine from working properly.

This medicine commonly causes nausea and sometimes causes vomiting. However, it may have to be taken for several weeks to months to be effective. Even if you begin to feel ill, do not stop using this medicine without first checking with your doctor. Ask your health care professional for ways to lessen these effects.

If you vomit shortly after taking a dose of estramustine, check with your doctor. You will be told whether to take the dose again or to wait until the next scheduled dose.

Dosing—

The dose of estramustine will be different for different patients. The dose that is used may depend on a number of things, including what the medicine is being used for, the patient's size, and whether or not other medicines are also being taken. If you are taking estramustine at home, follow your doctor's orders or the directions on the label. If you have any questions about the proper dose of estramustine, ask your doctor.

Missed dose—

If you miss a dose of this medicine, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store in the refrigerator, away from direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

It is very important that your doctor check your progress at regular visits to make sure that the medicine is working properly and does not cause unwanted effects.

While you are being treated with estramustine, and after you stop treatment with it, do not have any immunizations (vaccinations) without your doctor's approval. Estramustine 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 household 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. 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.

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. If your doctor is not available, go to the nearest hospital emergency room.

• Rare
  • Black, tarry stools;  blood in urine or stools;  cough or hoarseness;  fever or chills;  headaches (severe or sudden);  loss of coordination (sudden);  lower back or side pain;  painful or difficult urination ;  pains in chest, groin, or leg (especially calf of leg);  pinpoint red spots on skin;  shortness of breath (sudden, for no apparent reason);  slurred speech (sudden);  unusual bleeding or bruising;  vision changes (sudden);  weakness or numbness in arm or leg 
  
  

Check with your doctor as soon as possible if any of the following side effects occur:

• More common
  • Swelling of feet or lower legs 
  
  

• Rare
  • Skin rash or fever;  unusual tiredness or weakness 
  
  

Other 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. However, check with your doctor if any of the following side effects continue or are bothersome or if you have any questions about them:

• More common
  • Breast tenderness or enlargement;  decreased interest in sex;  diarrhea;  nausea 
  
  

• Less common
  • Trouble in sleeping;  vomiting 
  
  

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