Toremifene has caused very serious (possibly fatal) heart rhythm problems (QT prolongation in the EKG, torsades de pointes). Get medical help right away if any of these rare but serious side effects occur: fast/irregular heartbeat, seizures, severe dizziness, or fainting. The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may affect the heart rhythm. Before using toremifene, tell your doctor or pharmacist of all the drugs you take (see also Drug Interaction section) and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).
Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using toremifene safely.
See also Warning section.
Before taking toremifene, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: bone cancer (metastases), blood disorders (such as anemia, low platelets), diabetes, stroke, blood clots (such as in the legs, lungs), heart disease (such as heart attack, irregular heartbeat), high blood pressure, liver disease, uterus problems such as endometrial hyperplasia.
This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
Tell your doctor if you will be having surgery or will be confined to a chair/bed for a long time (such as on a long plane flight).
During pregnancy, toremifene should be used only when clearly needed. It may harm an unborn baby. If you become pregnant or think you may be pregnant, inform your doctor right away. Women of childbearing age should use reliable forms of non-hormonal birth control (such as condoms, diaphragm with spermicide) while using this medication. Discuss the use of birth control, the risks and benefits of this medication, and any other concerns about using this medication with your doctor.
It is unknown if this medication passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this medication. Consult your doctor before breastfeeding.
See also Warning section.
Hot flashes, sweating, nausea, vomiting, dry eyes, or dizziness may occur. If any of these side effects last or get worse, tell your doctor promptly.
Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including: bone/joint/muscle pain or swelling, constipation, mental/mood changes (such as depression), trouble walking/clumsiness, swelling ankles/feet, unusual tiredness, vision changes (such as blurred vision, eye pain), easy bleeding/bruising, signs of infection (such as sore throat that doesn't go away, fever, chills), symptoms of liver disease (such as nausea/vomiting that doesn't stop, loss of appetite, stomach/abdominal pain, yellowing eyes/skin, dark urine).
Toremifene may increase your risk of uterine cancer. Tell your doctor right away if you develop changes in menstrual period, unusual vaginal bleeding/discharge or pain/pressure below your "belly button" (navel).
Toremifene may rarely cause serious (sometimes fatal) problems from blood clots (such as heart attack, stroke, blood clots in the lungs or legs). Get medical help right away if you have: pain/swelling/warmth in the groin/calf, chest/jaw/left arm pain, confusion, sudden dizziness/fainting, sudden/severe headaches, trouble speaking, sudden vision changes, shortness of breath/rapid breathing, unusual sweating, weakness on one side of the body.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
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