Tamoxifen (Oral route)

Pronunciation:

ta-MOX-i-fen

Brand Names:

  • Nolvadex
  • Soltamox

Dosage Forms:

  • Solution
  • Tablet

Warnings:

Oral route(Solution)

Serious, life-threatening, and fatal events from use of tamoxifen include uterine malignancies, stroke, and pulmonary embolism. Discuss risks and benefits of tamoxifen with women at high risk for breast cancer and women with ductal carcinoma in situ (DCIS) when considering tamoxifen use to reduce the risk of developing breast cancer. For most patients already diagnosed with breast cancer, the benefits of tamoxifen outweigh its risks .

Oral route(Tablet)

Serious and life-threatening uterine malignancies, stroke, and pulmonary embolism have been associated with tamoxifen use in the risk reduction setting (women with Ductal Carcinoma in Situ (DCIS) and women at high risk for breast cancer). Some of these adverse events were fatal. Health care providers should discuss the potential benefits versus the potential risks of these serious events with women at high risk of breast cancer and women with DCIS considering tamoxifen to reduce their risk of developing breast cancer. The benefits of tamoxifen outweigh its risks in women already diagnosed with breast cancer .

Classifications:

Therapeutic—

Antiestrogen

Uses of This Medicine:

Tamoxifen is used to treat certain types of breast cancer (eg, estrogen receptor-positive breast cancer that has spread to other parts of the body [metastatic], early stage estrogen receptor-positive breast cancer after surgery and radiation treatment). It is also used to reduce the risk of invasive breast cancer in adult women with ductal carcinoma in situ (DCIS) after breast surgery and radiation treatment.

Tamoxifen is also used to reduce the risk for breast cancer in women with a high chance of getting it. The following are risk factors that may increase your risk of developing breast cancer:

  • If you have close family members (mother, sister, or daughter) with breast cancer.
  • If you have ever had a breast biopsy or if high-risk changes in your breast(s) have been found from a breast biopsy.
  • If you have never been pregnant or if your first pregnancy occurred at a late age.
  • If your first menstrual period occurred at an early age.

Female hormones called estrogen, that occur naturally in the body can increase the growth of some breast cancers. Tamoxifen works by blocking the effects of estrogen in the body.

This medicine is available only with your doctor's prescription.

Before Using This Medicine:

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

Allergies—

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Children—

Appropriate studies have not been performed on the relationship of age to the effects of tamoxifen in the pediatric population. Safety and efficacy have not been established.

Older adults—

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of tamoxifen in the elderly.

Breast-feeding—

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

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. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

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.

  • Acenocoumarol
  • Amisulpride
  • Bepridil
  • Cisapride
  • Dronedarone
  • Fluconazole
  • Ketoconazole
  • Mesoridazine
  • Nelfinavir
  • Phenprocoumon
  • Pimozide
  • Piperaquine
  • Posaconazole
  • Saquinavir
  • Sparfloxacin
  • Terfenadine
  • Thioridazine
  • Warfarin
  • 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.

  • Abiraterone Acetate
  • Amiodarone
  • Anagrelide
  • Aripiprazole
  • Aripiprazole Lauroxil
  • Arsenic Trioxide
  • Buprenorphine
  • Buserelin
  • Capecitabine
  • Carbamazepine
  • Ceritinib
  • Chloroquine
  • Cinacalcet
  • Clarithromycin
  • Clobazam
  • Clofazimine
  • Clozapine
  • Conivaptan
  • Crizotinib
  • Cyclophosphamide
  • Dabrafenib
  • Darunavir
  • Dasatinib
  • Degarelix
  • Delamanid
  • Deslorelin
  • Deutetrabenazine
  • Domperidone
  • Donepezil
  • Doxepin
  • Doxifluridine
  • Efavirenz
  • Encorafenib
  • Entrectinib
  • Enzalutamide
  • Escitalopram
  • Fingolimod
  • Fluorouracil
  • Fluoxetine
  • Fluvoxamine
  • Foscarnet
  • Fosnetupitant
  • Fosphenytoin
  • Genistein
  • Glasdegib
  • Gonadorelin
  • Goserelin
  • Histrelin
  • Hydroxychloroquine
  • Hydroxyzine
  • Inotuzumab Ozogamicin
  • Ipriflavone
  • Ivabradine
  • Ivosidenib
  • Lenvatinib
  • Leuprolide
  • Levofloxacin
  • Lofexidine
  • Lumacaftor
  • Macimorelin
  • Methadone
  • Methotrexate
  • Metronidazole
  • Mitomycin
  • Mitotane
  • Moclobemide
  • Moxifloxacin
  • Nafarelin
  • Netupitant
  • Nilotinib
  • Ondansetron
  • Osimertinib
  • Panobinostat
  • Paroxetine
  • Pasireotide
  • Pazopanib
  • Phenytoin
  • Pimavanserin
  • Pitolisant
  • Quetiapine
  • Quinine
  • Red Clover
  • Ribociclib
  • Rifampin
  • Rolapitant
  • Sertraline
  • Sevoflurane
  • Siponimod
  • Sotalol
  • St John's Wort
  • Sulpiride
  • Tacrolimus
  • Tegafur
  • Trazodone
  • Triclabendazole
  • Triptorelin
  • Vandetanib
  • Vemurafenib
  • Vinflunine
  • Zuclopenthixol

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Aldesleukin

Other interactions—

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems—

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Blood clots (eg, deep vein thrombosis, pulmonary embolism) or history of—Should not be used in patients with this condition.
  • Eye or vision problems (eg, cataracts) or
  • Hypercalcemia (high calcium levels in the blood) or
  • Hyperlipidemia (high cholesterol levels in the blood) or
  • Liver disease or
  • Stroke, history of—Use with caution. May make these conditions worse.

Proper Use of This Medicine:

Use this medicine only as directed by your doctor. Do not use more of it, do not use it more often, and do not take it for a longer time than your doctor ordered.

Medicines used to treat cancer are very strong and can have many side effects. Before using this medicine, make sure you understand all the risks and benefits. It is important for you to work closely with your doctor during your treatment.

This medicine comes with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions.

Shake the oral liquid well before each use. Measure the medicine with a marked medicine cup. The average household teaspoon may not hold the right amount of liquid.

Swallow the tablets whole with a glass of water. Do not break, divide, crush, or chew it. You can take the tablets with or without food.

Tamoxifen sometimes causes mild nausea and vomiting. However, it may have to be taken for several weeks or months to be effective. Even if you begin to feel ill, do not stop using this medicine without first checking with your doctor. Ask your health care professional for ways to lessen these effects.

Dosing—

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (solution, tablets):
    • For breast cancer:
      • Adults—20 to 40 milligrams (mg) per day. Doses greater than 20 mg are given as 2 divided doses per day (morning and evening).
      • Children—Use and dose must be determined by your doctor.
    • For breast cancer as additional treatment:
      • Adults—20 milligrams (mg) per day for 5 to 10 years.
      • Children—Use and dose must be determined by your doctor.
    • For reducing the risk of developing breast cancer in high-risk women:
      • Adults—20 milligrams (mg) per day for 5 years.
      • Children—Use and dose must be determined by your doctor.
    • For reducing the risk of developing invasive breast cancer in women with ductal carcinoma in situ:
      • Adults—20 milligrams (mg) per day for 5 years.
      • Children—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Do not store the oral liquid in the refrigerator or freezer. Throw away any unused liquid after 3 months of first opening the bottle.

Precautions While Using This Medicine:

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Do not use this medicine together with blood thinners (eg, warfarin).

Your doctor will give you a pregnancy test before you use this medicine to make sure you are not pregnant. Using this medicine while you are pregnant can harm your unborn baby. Birth control pills may not work as well to prevent pregnancy when used with this medicine. Use another form of birth control (eg, condoms, spermicide) along with your pills during treatment and for 2 months after the last dose. If you think you have become pregnant while using the medicine, tell your doctor right away.

This medicine may increase your risk for other cancers, including endometrium, liver, or uterus cancer. Tell your doctor if you have any changes in your menstrual period, such as irregular menstrual periods or no menstrual periods, or abnormal vaginal bleeding. It is important for women to have regular gynecologic check-ups while using this medicine. Talk to your doctor if you have concerns.

This medicine may increase your risk of developing blood clots. Check with your doctor right away if you have swelling and pain in your arms, legs, or stomach, chest pain, shortness of breath, loss of sensation, confusion, or problems with muscle control or speech.

This medicine may lower the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.

Check with your doctor right away if blurred vision, difficulty with reading, or any other change in vision occurs during or after treatment. Your doctor may want your eyes be checked by an ophthalmologist (eye doctor).

Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects of This Medicine:

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:

More common
Absent, missed, or irregular menstrual periods
bladder pain
blindness
bloating or swelling of the face, arms, hands, lower legs, or feet
bloody or cloudy urine
blurred vision
chills
confusion
cough
decrease in the amount of urine
decrease in height
decreased vision
difficult or labored breathing
difficult, burning, or painful urination
dizziness
fainting
fast heartbeat
fever
frequent urge to urinate
heavy non-menstrual vaginal bleeding
hoarseness
increased clear or white vaginal discharge
lower back or side pain
noisy, rattling breathing
pain in the back, ribs, arms, or legs
painful or difficult urination
pale skin
rapid weight gain
rapid, shallow breathing
stopping of menstrual bleeding
tightness in the chest
tingling of the hands or feet
troubled breathing at rest
troubled breathing with exertion
unusual bleeding or bruising
unusual tiredness or weakness
unusual weight gain or loss
Less common
Abnormal growth filled with fluid or semisolid material
black, tarry stools
bleeding gums
bloating
blurred vision
breast pain, redness, or swelling
chest pain
clear or bloody discharge from the nipple
cough producing mucus
dimpling of the breast skin
feeling of warmth or heat
flushing or redness of the skin, especially on the face and neck headache
inverted nipple
joint pain or stiffness
large amount of cholesterol in the blood
lump in the breast or under the arm
nervousness
persistent crusting or scaling of the nipple
pinpoint red spots on the skin
pounding in the ears
skin rash or itching over the entire body
slow heartbeat
sore on the skin of the breast that does not heal
stomach or pelvic discomfort, aching, or heaviness
Rare
Anxiety
bluish color of the skin
tenderness
Incidence not known
Blistering, peeling, loosening of the skin
constipation
dark urine
diarrhea
general feeling of discomfort or illness
indigestion
muscle pain
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
loss of appetite
nausea
pains in the stomach, side, or abdomen, possibly radiating to the back
red skin lesions, often with a purple center
red, irritated eyes
sore throat
sores, ulcers, or white spots in the mouth or on the lips
thickening of bronchial secretions
vomiting
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
Back pain
belching
body aches or pain
bone pain
congestion
depression
difficulty in moving
dryness of the throat
hair loss or thinning of hair
heartburn
joint swelling
lack or loss of strength
mood changes
muscle cramps or stiffness
passing of gas
redness of the face, neck, arms, and occasionally, upper chest
runny nose
shivering
skin changes
stomach upset, fullness, or pain
sudden sweating
tender, swollen glands in the neck
trouble in swallowing
trouble sleeping
voice changes
Less common
Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
itching of the vagina or genital area
pain during sexual intercourse
Incidence not known
Decreased interest in sexual intercourse
inability to have or keep an erection
loss in sexual ability, desire, drive, or performance

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.


Last Updated: 9/5/2019

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The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites.
All rights reserved.

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