In this drug factsheet:
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- back pain
- breast tenderness
- change in sex drive
- contact lens discomfort
- darkening of the skin around areas where the patch is applied
- dry eyes
- excessive hair growth
- hair loss
- increased vaginal secretions
- memory problems
- redness or irritation underneath or around the area of the skin on which the patch is applied
- trouble sleeping
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- breast lumps
- discharge from nipple
- easy bruising
- frequent or prolonged, exceptionally heavy periods
- flu-like symptoms
- fluid retention (swelling of the lower legs, ankles, feet, or fingers)
- high blood pressure
- lower abdominal pain or swelling, painful or heavy periods
- migraine headache
- symptoms of an infection (e.g., fever)
- signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
- signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
- symptoms of gallstones (e.g., pain in the upper right abdomen, pain between the shoulder blades or in the right shoulder)
- symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)
Stop taking the medication and seek immediate medical attention if any of the following occur:
- coughing blood
- headache (sudden or severe)
- signs of a heart attack (e.g., chest pain or pressure, pain extending through shoulder and arm, nausea and vomiting, sweating)
- sudden shortness of breath, coughing up blood, or sharp pain in chest
- sudden vision changes (such as partial or complete loss of vision, double vision)
- symptoms of a severe allergic reaction (e.g., hives; difficult breathing; swelling of the face, mouth, throat, or tongue)
- symptoms of a stroke (e.g., sudden and severe headache, sudden vision changes, sudden difficulty speaking, sudden weakness or numbness in arms or legs, sudden dizziness, fainting, or vomiting)
- tender or painful inflammation of the veins (e.g., pain in groin, calf)
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Note the following important information about estrogen replacement therapy:
The Women's Health Initiative (WHI) study results indicated an increased risk of heart attack, stroke, breast cancer, blood clots in the lungs, and blood clots in the leg veins in postmenopausal women during 5 years of treatment with 0.625 mg conjugated equine estrogens and 2.5 mg medroxyprogesterone compared to women receiving sugar tablets. Other combinations of estrogen and progestins were not studied. However, until additional data are available, the risks should be assumed to be similar for other hormone replacement products. Therefore,
- estrogens with or without progestins should be used at the lowest dose that relieves your menopausal symptoms for the shortest time period possible, as directed by your doctor.
- estrogens with or without progestins should not be used to prevent heart disease, heart attacks, or strokes
Allergy: Contact allergy, such as itching and redness, is known to occur with the application of estrogen to the skin. Although this allergy is extremely rare, people who develop skin reactions or contact sensitization to any component of the medication are at risk of developing a severe allergic reaction with continued use. If you have a skin reaction to the patch, contact your doctor for advice.
Blood clotting disorders: Estrogens with or without progestins are associated with an increased risk of blood clots in the lungs (pulmonary embolism) and legs (deep vein thrombosis). If you have or have had a heart attack, a stroke, heart disease, a blood clot in your leg, or have medical conditions that increase your risk of blood clots, you should not use this medication.
The risk of developing blood clots also increases with age, a personal or family history of blood clots, smoking, and obesity. It is also increased if you are immobilized for prolonged periods and with major surgery. If possible, this medication should be stopped 4 weeks before major surgery. Talk about the risk of blood clots with your doctor.
Blood pressure: Women may experience increased blood pressure when using estrogen replacement therapy. Talk to your doctor about how often you should have your blood pressure checked.
Bone disease: If you have bone disease due to cancer or a metabolic condition causing too much calcium in your body, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Breast and ovarian cancer: Studies indicate an increased risk of breast and ovarian cancer with long-term use of estrogen replacement therapy. Women with a history of breast cancer should not use estrogens. Women who have breast nodules, fibrocystic disease, abnormal mammograms, or a strong family history of breast cancer should be closely monitored by their doctor.
Women taking estrogens should have regular breast examinations and should be instructed in breast self-examination. The estradiol patch must not be applied to the breasts, as it may have harmful effects on the breast tissue.
Dementia: Women over the age of 65 receiving combined hormone replacement therapy (estrogen and progestin) may be at increased risk of developing dementia (loss of memory and intellectual function). If you are over 65, talk to your doctor about whether you should be tested for dementia.
Diabetes: Estrogens may affect blood sugar control. If you have diabetes or are at risk of developing diabetes (e.g., have a family history of diabetes, have high blood pressure or high cholesterol, or are obese), carefully monitor your blood glucose levels while using this medication.
Endometrial cancer: There is evidence from several studies that estrogen replacement therapy can increase the risk of cancer of the endometrium (lining of the uterus). Taking a progestin at the right time along with the estrogen reduces this risk of endometrial cancer to the same level as that of a woman who does not take estrogen. For this reason, all women who have not had their uterus removed should also take a progestin if they are using estrogens.
If you develop any abnormal vaginal bleeding while using this medication, contact your doctor. If you have or have had endometrial cancer, you should not use this medication.
Endometriosis: Estrogen replacement therapy can cause endometriosis to reappear or get worse. If you have or have had endometriosis, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Fibroids: This medication may worsen fibroids by causing sudden enlargement, pain, or tenderness. If you notice these effects, contact your doctor.
Fluid retention: Estrogen may cause fluid retention, and worsen heart disease, kidney disease, or asthma. Talk to your doctor if you have any concerns. If you experience worsening of these conditions while using this medication, contact your doctor.
Follow-up examinations: It is important to have a follow-up examination 3 to 6 months after starting this medication to assess your response to treatment. Examinations should be done at least once a year after the first one.
Gallbladder disease: This medication can aggravate gallbladder disease or increase the risk of developing it. If you have gallbladder disease, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Heart disease and stroke: Studies indicate an increased risk of heart disease and stroke with estrogen (with or without progestin) for postmenopausal women. If you experience symptoms of a heart attack (chest pain, tightness or pressure, sweating, nausea, feeling of impending doom) or stroke (sudden dizziness, headache, loss of speech, changes in vision, weakness or numbness in the arms and legs) while taking this medication, get immediate medical attention.
High cholesterol or triglycerides: Estrogen may increase triglyceride levels in those who already have high levels. This has been observed particularly when estrogen is taken orally – the risk is reduced with use of the patch. Your doctor will monitor your cholesterol and triglyceride levels while you are taking this medication.
Kidney function: Estrogen can affect how calcium and phosphorus are used by your body. If you have kidney disease, this may be a concern and you should discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Liver function: If you have reduced liver function, you may require special monitoring by your doctor while you use this medication. Make sure to tell your doctor if you have ever had liver problems. People with active liver disease or liver tumours should not use the estradiol patch.
If you experience symptoms of liver problems (e.g., yellowing of the skin or eyes, abdominal pain, loss of appetite, dark urine, pale stools, nausea, or vomiting), contact your doctor immediately.
Migraine headaches: If you have migraines with aura (headache is associated with symptoms such as flashes of light, tingling sensations, blind spots, muscle weakness, difficulty speaking either before or during the headache), you should not use this medication.
For some people who experience migraine headaches, estrogen can aggravate the condition. Talk to your doctor if you notice any change in your migraine pattern while using estrogen.
Seizures: Estrogens may increase your risk of having a seizure. If you have a seizure disorder or a history of seizures, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Thyroid disease: Estrogen may affect how thyroid hormone is used by the body. If you are taking thyroid medication to supplement an underactive thyroid gland, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Pregnancy: Estrogen should not be used during pregnancy. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: This medication passes into breast milk. If you are a breast-feeding mother and are taking estrogen, it may affect your baby. This medication is not recommended for breast-feeding women.
Children: The safety and effectiveness of using this medication have not been established for children.
What other drugs could interact with this medication?
There may be an interaction between the estradiol patch and any of the following medications:
- antidiabetes medication (e.g., insulin, metformin, glyburide)
- ascorbic acid (Vitamin C)
- "azole" antifungals (e.g., itraconazole, ketoconazole, voriconazole)
- barbiturates (e.g. pentobarbital, phenobarbital)
- oral corticosteroids (e.g., dexamethasone, prednisolone, prednisone)
- grapefruit juice
- HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., efavirenz, etravirine, nevirapine)
- HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
- low molecular weight heparins (e.g., dalteparin, enoxaparin, tinzaparin)
- macrolide antibiotics (e.g., clarithromycin, erythromycin)
- medications used to treat high blood pressure (e.g., atenolol, rampiril, enalapril, lisinopril, amlodipine)
- St. John's wort
- saw palmetto
- thyroid replacements (e.g., dessicated thyroid, levothyroxine)
- tyrosine kinase inhibitors (e.g., dasatinib, imatinib, nilotinib, sunitinib)
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.