Before Using This Medicine

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 pentosan, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to pentosan. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Diet—It is important that you follow any special instructions from your doctor. Some foods and beverages may aggravate your condition. Also, make certain your health care professional knows if you are on any special diet, such as a low-sodium or low-sugar diet.

Pregnancy—Pentosan has not been shown to cause birth defects or other problems in humans. However, studies in animal tissues have shown that pentosan may be harmful to the fetus. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—It is not known whether pentosan passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of pentosan in children with use in other age groups.

Older adults—This medicine has been tested and has not been shown to cause different side effects or problems in older people than it does in younger adults.

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

• Alteplase or
• Anticoagulants (blood thinners) or
• Aspirin, high doses or
• Heparin or
• Streptokinase—Taking these medicines with pentosan may increase the risk of bleeding

Other medical problems—The presence of other medical problems may affect the use of pentosan. Make sure you tell your doctor if you have any other medical problems, especially:

• Blood or blood vessel disease or other blood problems or
• Blockage or obstruction of the intestine or
• Polyps or
• Stomach ulcers—The risk of bleeding may be increased
• Liver disease or
• Spleen problems—Pentosan may not be broken down in the body as fast as it normally would; the chance of side effects may be increased