toremifene
Toremifene (Fareston) is a type of hormone therapy used to treat hormone-receptor positive (HR+) metastatic breast cancer in postmenopausal females. It’s an oral tablet that’s conveniently taken once a day, but it’s not used as commonly as other similar medications. You’ll also need to look out for signs and symptoms of dangerous heart rhythm changes.
What is Toremifene (Fareston)?
What is Toremifene (Fareston) used for?
Metastatic HR+ breast cancer or tumors in which estrogen status is not known in postmenopausal females
How Toremifene (Fareston) works
Toremifene (Fareston) is a selective estrogen receptor modulator. Some breast cancers rely on the hormone estrogen to grow. These breast cancers are called hormone-receptor positive (HR+).
Toremifene (Fareston) works to treat HR+ breast cancer by blocking estrogen from working on breast tissue. By blocking estrogen, cancer cells don’t have the fuel they need to grow, which stops breast cancer from growing and spreading.
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What are the side effects of Toremifene (Fareston)?
Common Side Effects
- Hot flashes (35%)
- Sweating (20%)
- Nausea (14%)
- Vaginal discharge (13%)
- Cataracts (10%)
- Dry eyes (9%)
Other Side Effects
- Changes in vision
- Dizziness
- Swelling
- Vomiting
Serious Side Effects
- Abnormal heart rhythm: feel your heart beating, weakness, blurred vision, lightheadedness
- Cancers of the uterus: abnormal vaginal bleeding, vaginal discharge, or pain or pressure in the area below your belly button (pelvis)
- Blood clots in your veins or lungs: pain or swelling in your arms or legs, trouble breathing, chest pain, fast heartbeat
Source: DailyMed
The following side effects have also been reported
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Less common
arm, back, or jaw pain
blurred vision
change in how much and how often you urinate
change in vaginal discharge
changes in skin color
changes in vision
changes in weight
chest pain, discomfort, tightness, or heaviness
confusion
dilated neck veins
dizziness, lightheadedness
fainting
fast, slow, or irregular heartbeat
inability to speak, incoherent speech
irregular breathing
loss of appetite
metallic taste in the tongue
muscle weakness
pain or discomfort in the arms, jaw, back, or neck
pain or feeling of pressure in the pelvis
pain, tenderness, or swelling of the foot or leg
seizures
severe or sudden headache
stomach pain
sweating
swelling of the face, fingers, feet, or lower legs
temporary blindness
tenderness, pain, swelling, warmth, skin discoloration, prominent superficial veins over the affected area
thirst
troubled breathing
unusual tiredness or weakness
vaginal bleeding
vomiting
weakness in the arm and or leg on one side of the body, sudden and severe
Incidence not known
Black, tarry stools
bleeding gums
blood in the urine or stools
chills
clay-colored stools
dark urine
painful or difficult urination
pinpoint red spots on the skin
rash
sores, ulcers, or white spots on the lips or in the mouth
swollen glands
unpleasant breath odor
unusual bleeding or bruising
vomiting of blood
yellow eyes or skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Blindness
decreased vision
feeling of warmth
redness of the face, neck, arms, and occasionally, the upper chest
sudden sweating
sweating
Incidence not known
Blistering, crusting, irritation, itching, or reddening of the skin
cracked, dry, or scaly skin
difficulty having a bowel movement
feeling of constant movement of self or surroundings
feeling unusually cold
lack or loss of strength
partial or slight paralysis
sensation of spinning
shakiness in the legs, arms, hands, or feet
thinning of the hair
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Pros and cons of Toremifene (Fareston)
Pros
Available as a lower-cost generic
Only needs to be taken once a day
Can be taken with or without food
Cons
Interacts with many medications
Raises the risk of dangerous changes in your heart rhythm
Requires periodic monitoring of complete blood counts, calcium levels, and liver health
Pharmacist tips for Toremifene (Fareston)
Take toremifene (Fareston) with or without food. And try to take it around the same time every day to keep a consistent level of medication in your body.
Avoid taking toremifene (Fareston) with grapefruit or grapefruit juice. Doing so could cause your body to absorb more of the medication, which raises your risk for more side effects.
Toremifene (Fareston) interacts with many medications. Some medications can either raise your risk for more side effects or cause toremifene (Fareston) to not work as well. Always let your healthcare provider know about all the medications you take, including supplements and OTC products.
Watch out for signs and symptoms of serious changes in your heart rhythm when taking toremifene (Fareston). These can include fainting, lightheadedness, and blurred vision. Also certain medications (e.g. amiodarone (Pacerone), venlafaxine (Effexor), clarithromycin) can further raise your risk of this potentially life-threatening side effect if taken together with toremifene (Fareston).
Toremifene (Fareston) can cause changes to your blood cell counts, calcium levels, and liver labs. Make sure to get regular lab work to check that your levels are healthy.
Frequently asked questions about Toremifene (Fareston)
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What are the risks and warnings for Toremifene (Fareston)?
Toremifene (Fareston) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Heart Rhythm problem
Risk factors: Long QT syndrome | Heart failure | Liver problems | Low potassium and magnesium levels | Taking other medications that cause heart rhythm problems
Toremifene (Fareston) can affect your heart rhythm by prolonging the time period from when the heart pumps and then relaxes. This is known as QT prolongation, which can be life-threatening. Your risk for QT prolongation is higher if you have certain risk factors, including low potassium or magnesium and heart rhythm problems, or are taking other medications that also cause QT prolongation. To lower your risk, your provider will periodically monitor your heart and do certain tests to make sure your heart rhythm is normal. If you can feel your heart beating, have weakness or blurred vision, or experience lightheadedness, go to the emergency room immediately.
Liver problems
Some people taking toremifene (Fareston) developed liver problems. These included inflammation of the liver (hepatitis), yellowing of the skin and eyes (jaundice), and non-alcoholic fatty liver disease. Your provider will monitor your liver health through lab work while you’re taking toremifene (Fareston). Let your provider know if you develop loss of appetite, nausea, vomiting, stomach pain, dark-colored urine, or yellowing of the skin and eyes. These can be symptoms of a problem with your liver.
Tumor flare
Risk factors: Cancer that has spread to your bones
Particularly in people whose cancer has spread to their bones, toremifene (Fareston) can cause a temporary side effect called a tumor flare, which can happen within the first few weeks of treatment. This is when your cancer gets bigger for a short time, but it usually shrinks back soon after. During this tumor flare, you might experience pain in your muscles or have some skin redness. You might also have higher calcium levels during this time. Your provider might monitor for this through lab work. If your calcium levels get too high, your provider might have you stop taking toremifene (Fareston).
Risk of developing cancer of the uterine lining
Risk factors: People at high risk for endometrial cancer
Toremifene (Fareston) can raise your risk of endometrial cancer (or cancers of the uterine lining) and other problems with your uterus (e.g., uterine polyps and enlargement of your uterus). Before you start taking toremifene (Fareston) and during treatment, your provider will perform a gynecological exam. Let your provider know if you have abnormal vaginal bleeding, vaginal discharge, or pain or pressure in the area below your belly button (pelvis). These can be signs of a problem with your uterus.
Blood clots
*Risk factors: Older age | Not moving much or on bed rest | History of blood clots *
Toremifene (Fareston) could raise your risk for blood clots in your body, that’s why it’s not recommended for people with a history of blood clots. Symptoms of a blood clot might be different depending on the location of the clot. They can include swelling, warmth, or tenderness in the legs. But more seriously, clots can lead to breathing problems and chest pain. Get medical attention right away if you have any of these symptoms.
Harm to unborn baby
Based on animal studies, toremifene (Fareston) might harm an unborn baby. Because of these risks, if you're a female who can get pregnant, you should use non-hormonal birth control, like condoms or a diaphragm, while taking toremifene (Fareston). Let your provider know right away if you become pregnant during this time.
Toremifene (Fareston) dosage forms
| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 60mg | 30 tablets | $161.74 | $5.39 |
Typical dosing for Toremifene (Fareston)
The typical dose is 60 mg taken by mouth once a day.
Interactions between Toremifene (Fareston) and other drugs
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
- Bepridil
- Cisapride
- Dronedarone
- Fluconazole
- Ketoconazole
- Mesoridazine
- Nelfinavir
- Pimozide
- Piperaquine
- Posaconazole
- Saquinavir
- Sparfloxacin
- Terfenadine
- Thioridazine
- Ziprasidone
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Alfuzosin
- Amiodarone
- Amisulpride
- Amitriptyline
- Amoxapine
- Anagrelide
- Apomorphine
- Aripiprazole
- Aripiprazole Lauroxil
- Arsenic Trioxide
- Asenapine
- Astemizole
- Atazanavir
- Azithromycin
- Boceprevir
- Buprenorphine
- Buserelin
- Ceritinib
- Chloroquine
- Chlorpromazine
- Ciprofloxacin
- Citalopram
- Clarithromycin
- Clofazimine
- Clomipramine
- Clozapine
- Cobicistat
- Conivaptan
- Crizotinib
- Dabrafenib
- Dasatinib
- Degarelix
- Delamanid
- Desipramine
- Deslorelin
- Deutetrabenazine
- Disopyramide
- Dofetilide
- Dolasetron
- Domperidone
- Donepezil
- Droperidol
- Efavirenz
- Encorafenib
- Entrectinib
- Erythromycin
- Escitalopram
- Fingolimod
- Flecainide
- Fluoxetine
- Formoterol
- Foscarnet
- Fostemsavir
- Gatifloxacin
- Gemifloxacin
- Glasdegib
- Gonadorelin
- Goserelin
- Granisetron
- Halofantrine
- Haloperidol
- Histrelin
- Hydroxychloroquine
- Hydroxyzine
- Ibutilide
- Idelalisib
- Iloperidone
- Imipramine
- Indinavir
- Inotuzumab Ozogamicin
- Itraconazole
- Ivabradine
- Ivosidenib
- Lapatinib
- Lefamulin
- Lenvatinib
- Levofloxacin
- Lofexidine
- Lopinavir
- Lumefantrine
- Macimorelin
- Mefloquine
- Methadone
- Metronidazole
- Mifepristone
- Mirtazapine
- Moxifloxacin
- Nafarelin
- Nefazodone
- Nilotinib
- Norfloxacin
- Nortriptyline
- Octreotide
- Ofloxacin
- Ondansetron
- Osilodrostat
- Osimertinib
- Oxaliplatin
- Ozanimod
- Paliperidone
- Panobinostat
- Pasireotide
- Pazopanib
- Pimavanserin
- Pitolisant
- Ponesimod
- Procainamide
- Prochlorperazine
- Promethazine
- Propafenone
- Protriptyline
- Quetiapine
- Quinidine
- Quinine
- Ranolazine
- Ribociclib
- Ritonavir
- Selpercatinib
- Sertraline
- Sevoflurane
- Siponimod
- Sodium Phosphate
- Solifenacin
- Sorafenib
- Sotalol
- Sugammadex
- Sulpiride
- Sunitinib
- Tacrolimus
- Telavancin
- Telithromycin
- Tetrabenazine
- Trazodone
- Triclabendazole
- Trifluoperazine
- Trimipramine
- Triptorelin
- Vandetanib
- Vardenafil
- Vemurafenib
- Venlafaxine
- Vinflunine
- Voclosporin
- Voriconazole
- Zuclopenthixol
How much does Toremifene (Fareston) cost?
Toremifene (Fareston) contraindications
Heart rhythm problems (QT syndrome)
Low potassium
Low magnesium
What are alternatives to Toremifene (Fareston)?
Metastatic HR+ breast cancer or tumors in which estrogen status is not known in postmenopausal females
Hormone receptor (HR)-positive, advanced or metastatic breast cancer
Early-stage HR+ breast cancer after surgery to lower the risk of breast cancer coming back
Ductal carcinoma in situ (DCIS) in females after breast surgery and radiation to lower the risk of breast cancer coming back
Lowering the risk of breast cancer in females who are considered high risk
Toremifene (Fareston) images
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