Before Receiving This Medicine

In deciding to use a medicine, the risks of using the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For thrombolytic agents, the following should be considered:

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

Pregnancy—Tell your doctor if you are pregnant or if you have recently had a baby.

There is a slight chance that use of a thrombolytic agent during the first five months of pregnancy may cause a miscarriage. However, both streptokinase and urokinase have been used in pregnant women and have not been reported to cause this problem. Also, studies in pregnant women (for streptokinase) and studies in animals (for urokinase) have not shown that these medicines cause either miscarriage or harm to the fetus (including birth defects). Studies on birth defects with alteplase and anistreplase have not been done in either pregnant women or animals.

Breast-feeding—It is not known whether thrombolytic agents pass into the 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 any of these medicines and who wish to breast-feed should discuss this with their doctor.

Children—Studies on these medicines have been done only in adult patients, and there is no specific information comparing the use of thrombolytic agents in children with use in other age groups. However, streptokinase has occasionally been used in children to dissolve blood clots in certain blood vessels. Bleeding may be more likely to occur in children, who are usually more sensitive than adults to the effects of streptokinase.

Older adults—The need for treatment with a thrombolytic agent (instead of other kinds of treatment) may be increased in elderly patients with blood clots. However, the chance of bleeding may also be increased. It is especially important that you discuss the use of this medicine with your doctor.

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. Before you receive a thrombolytic agent, it is especially important that your doctor know if you are taking any of the following:

• Anticoagulants (blood thinners) or
• Aspirin or
• Cefamandole (e.g., Mandol) or
• Cefoperazone (e.g., Cefobid) or
• Cefotetan (e.g., Cefotan) or
• Dipyridamole (e.g., Persantine)
• Divalproex (e.g., Depakote) or
• Enoxaparin (e.g., Lovenox) or
• Heparin or
• Indomethacin (e.g., Indocin) or
• Inflammation or pain medicine (except narcotics) or
• Phenylbutazone (e.g., Butazolidin) or
• Plicamycin (e.g., Mithracin) or
• Sulfinpyrazone (e.g., Anturane) or
• Thrombolytic agents, other or
• Ticlopidine (e.g., Ticlid) or
• Valproic acid (e.g., Depakene)—The chance of bleeding may be increased

Also, tell your doctor if you have had an injection of anistreplase or streptokinase within the past year. If you have, these medicines may not work properly if they are given to you again. Your doctor may decide to use alteplase or urokinase instead.

Other medical problems—The presence of other medical problems or recent delivery of a child may affect the use of thrombolytic agents. Make sure you tell your doctor if you have any other medical problems, especially:

• Allergic reaction to streptokinase, anistreplase, or urokinase (or history of)—Increased risk of an allergic reaction
• Blood disease, bleeding problems, or a history of bleeding in any part of the body or
• Brain disease or tumor or
• Heart or blood vessel disease, including irregular heartbeat or
• High blood pressure or
• Liver disease (severe) or
• Stroke, especially with seizure (or history of)—The chance of serious bleeding may be increased

• Streptococcal (“strep”) infection (recent)
• Surgery within the last two months—Anistreplase or streptokinase may not work properly after a streptococcal infection; your doctor may decide to use a different thrombolytic agent

Also, tell your doctor if you have recently had any of the following conditions:

• Falls or blows to the body or head or any other injury or
• Injections into a blood vessel or
• Placement of any tube into the body or
• Surgery, including dental surgery—The chance of serious bleeding may be increased

If you have recently had a baby, use of these medicines may cause serious bleeding.