What is this medication?
TESTOLACTONE (TES toe LAK tone) blocks the body from making estrogen. It is used to treat advanced breast cancer in women.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Teslac
What should I tell my care team before I take this medication?
They need to know if you have any of these conditions:
•an unusual or allergic reaction to testolactone, other medicines, foods, dyes, or preservatives
•pregnant or trying to get pregnant
How should I use this medication?
Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take your doses at regular intervals. Do not take your medicine more often than directed.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses. Tell your doctor if you miss a dose of this medicine.
What may interact with this medication?
•female hormones, like estrogens or progestins and birth control pills
•some herbal products with estrogen or estrogen-like ingredients
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medication?
Visit your doctor for regular check ups. Tell your doctor if you have any unusual effects while you are taking this medicine. You will need important blood work done while you are taking this medicine.
What side effects may I notice from receiving this medication?
Side effects that you should report to your doctor or health care professional as soon as possible:
•allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
•high blood pressure
•numbness, prickling, tingling
•swelling of arms, legs
•unusually weak or tired
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
•aches in arms and legs
•irregular nail growth
•loss of appetite
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medication?
Keep out of the reach of children. This medicine can be abused. Keep your medicine in a safe place to protect it from theft. Do not share this medicine with anyone. Selling or giving away this medicine is dangerous and against the law.
Store at room temperature of 25 degrees C (77 degrees F). Throw away any unused medicine after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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