What other drugs will affect Doctamoxifene?
Many drugs can interact with Doctamoxifene, and some drugs should not be used together. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide. Tell your doctor about all medicines you use, and those you start or stop using during your treatment with Doctamoxifene. Give a list of all your medicines to any healthcare provider who treats you.
Side effects of Doctamoxifene
DocDoctamoxifenee's selective estrogen activation effects can cause some serious side effects, including blood clots, stroke, and endometrial cancer. If you and your doctor are considering Doctamoxifene as part of your treatment plan, tell your doctor if you smoke or have a history of blood clots or heart attack. If you're taking Doctamoxifene, call your doctor immediately if you have any of these symptoms:
- abnormal vaginal bleeding or discharge
- pain or pressure in the pelvis
- leg swelling or tenderness
- chest pain
- shortness of breath
- weakness, tingling, or numbness in your face, arm, or leg
- difficulty speaking or understanding
- vision problems
- sudden severe headache
The most common side effects of Doctamoxifene are:
Hot flashes or night sweats from taking Doctamoxifene can be troubling. But a 2008 British study suggests that women who experienced hot flashes and night sweats while taking hormonal therapy medicine were less likely to have the breast cancer come back (recur). Knowing that this side effect might indicate a reduced risk of the cancer coming back may help some people stick with treatment despite the side effects.
Some women on Doctamoxifene have reported memory problems while taking the medicine. While no definitive results are available yet, the ongoing Co-STAR (Cognition in the Study of DocDoctamoxifenee and Raloxifene) trial is looking at the effects Doctamoxifene and raloxifene have on memory and thinking.
DocDoctamoxifenee may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- increased bone or tumor pain
- pain or reddening around the tumor site
- hot flashes
- excessive tiredness
- thinning of hair
- weight loss
- stomach cramps
- loss of sexual desire or ability (in men)
Medicines to avoid while taking Doctamoxifene
In the list below, the medications under the headings “Strong Inhibitors” and “Moderate Inhibitors” can inhibit CYP2D6 and interfere with the effectiveness of Doctamoxifene. The medications under the heading “Not Inhibitors” do not block the CYP2D6 enzyme and will not interfere with Doctamoxifene treatment.
This list is incomplete and subject to change over time. Use it as a starting place and ask your doctor if any medications you are taking or that are recommended to you are compatible with Doctamoxifene.
Source: Coprescription of DocDoctamoxifenee and Medications That Inhibit CYP2D6. Kostandinos Sideras, James N. Ingle, Matthew M. Ames, Charles L. Loprinzi, David P. Mrazek, John L. Black, Richard M. Weinshilboum, John R. Hawse, Thomas C. Spelsberg, and Matthew P. Goetz. Journal of Clinical Oncology 2010 28:16, 2768-2776Flockhart.
What is the dosage for Doctamoxifene (Soltamox)?
- The dose for metastatic breast cancer treatment, DCIS, and prevention of breast cancer is 10 mg twice daily or 20 mg once daily for 5 years.
- The dose for stimulation of ovulation is 5-40 mg twice daily for 4 days.
- DocDoctamoxifenee can be taken with food.
Q: Are there any side efects of taking Doctamoxifene over a five year period?
A: DocDoctamoxifenee is a medication that is used to treat or prevent breast cancer. DocDoctamoxifenee is in the group of medications called selective estrogen receptor modulator or SERMs. DocDoctamoxifenee interferes with the activity of estrogen, that may promote the growth of breast cancer. Some breast cancers are classified as estrogen receptor positive which means they have a protein that estrogen binds to. These breast cancers depend on estrogen to grow and Doctamoxifene works against the effects of estrogen on these cells. The prescribing information on Doctamoxifene lists the following as the most common side effects of the medication: hot flashes, headaches, fatigue, nausea/vomiting, vaginal dryness, and skin rash. The side effects are similar to those experienced during menopause. The prescribing information on Doctamoxifene states that depending on your type of breast cancer the treatment length will vary. Patients with metastatic breast cancer may take Doctamoxifene for long periods of time depending on the cancer's response to the medication. When used in patients with early stage breast cancer, Doctamoxifene is generally prescribed for 5 years. DocDoctamoxifenee has been linked to endometrial cancer is some women, and the length of time taking the medication increases the risk. Patients who do not have a uterus are not at risk. This is one of the main reasons that Doctamoxifene is not taken for longer than 5 years. Cataracts are a common eye issue as we age, but it is found that Doctamoxifene can increase the risk of developing this condition. If you are taking chemotherapy medications while taking Doctamoxifene, there is a small increase in the risk for developing blood clots. The total number of women who experienced this side effect was very small. The risk is similar to taking estrogen hormone replacement therapy. Lori Poulin, PharmD
Q: About three weeks ago I started having cramps in the backs of my legs. It only happens in the morning when I'm ready to get up. I've just started taking Doctamoxifene. Are the cramps one its possible side effects?
A: Leg cramps are a common complaint among patients who take Doctamoxifene. It may help to make sure you stay hydrated throughout the day, and increase your intake of foods containing potassium. You can also ask your physician if drinking tonic water would be an acceptable treatment, since tonic water contains small amounts of quinine, which may take the edge off your cramps. In any case, discuss this side effect with your physician. For more information about Doctamoxifene, go to //www.everydayhealth.com/drugs/Doctamoxifene. Matt Curley, PharmD
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug are: anastrozole, "blood thinners" (e.g., warfarin), estrogens, letrozole, hormonal forms of birth control (e.g., birth control pills, patches, implants), ribociclib.
Other medications can affect the removal of Doctamoxifene from your body, which may affect how Doctamoxifene works. Examples include cimetidine, rifamycins (e.g., rifampin), SSRI antidepressants (e.g., fluoxetine, paroxetine), St. John's wort, drugs used to treat seizures (e.g., carbamazepine, phenobarbital, phenytoin, primidone), among others.
This medication may interfere with certain laboratory tests (including thyroid tests), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.
Is Doctamoxifene (Soltamox) safe to use during pregnancy or while breastfeeding?
- DocDoctamoxifenee should not be used during pregnancy because it can harm the fetus.
- It is not known whether Doctamoxifene is excreted in breast milk. DocDoctamoxifenee causes a reduction in milk production. Women taking Doctamoxifene should not breastfeeding.
The liquid form of Doctamoxifene contains a very small amount of alcohol. This is not harmful to most people but may be a problem if you have alcoholism.
Before taking this medicine
You should not use Doctamoxifene if you are allergic to it.
You should not use Doctamoxifene to reduce your risk of breast cancer if you are also taking a blood thinner such as warfarin (Coumadin, Jantoven).
Do not take Doctamoxifene if you are pregnant. It could harm the unborn baby. Avoid becoming pregnant while you are using this medicine, and for at least 2 months after your treatment ends.
Hormonal contraception (such as birth control pills, injections, implants, skin patches, and vaginal rings) may not be effective enough to prevent pregnancy while taking Doctamoxifene. Use barrier or non-hormonal birth control (examples: condom, diaphragm with spermicide, or intrauterine device/IUD).
If you are taking Doctamoxifene to reduce your risk of breast cancer, you may need to take your first dose while you are having a menstrual period. You may also need to have a pregnancy test before you start taking Doctamoxifene, to make sure you are not pregnant. Follow your doctor's instructions.
Taking Doctamoxifene may increase your risk of uterine cancer, stroke, or a blood clot in the lung, which can be fatal. Talk with your doctor about your specific risks in taking this medicine.
To make sure Doctamoxifene is safe for you, tell your doctor if you have:
a history of stroke or blood clot;
high cholesterol or triglycerides (a type of fat in the blood);
a history of cataracts; or
if you are receiving chemotherapy or radiation.
It is not known whether Doctamoxifene passes into breast milk or if it could harm a nursing baby. This medicine has been shown to slow breast milk production. Do not breast-feed while taking Doctamoxifene.
It can be a treatment or a prevention
DocDoctamoxifenee is in a class of drugs known as selective estrogen receptor modulators, or SERMs. These drugs work by attaching to estrogen receptors in breast cells, blocking estrogen’s ability to cause cell mutations that lead to cancer.
The drug—taken as a pill or a liquid—is often prescribed to pre-menopausal women after surgery for early-stage breast cancer. Because surgeons can’t always be sure they removed all of the cancer cells, Doctamoxifene can reduce the risk that those leftover cells will continue to multiply and the cancer will return.
It can also be prescribed to women, pre- or post-menopause who have not been diagnosed with breast cancer, if they have a high risk (1.67% or higher) of developing it over the next five years. These women are usually 35 or older, and have risk factors such as a family history of cancer or a history of abnormal biopsies.
Mechanism of Injury
The acute form of liver injury attributed to Doctamoxifene use is probably due to an idiosyncratic reaction to a metabolite of the medication rather than its estrogenic effects. In contrast, the induction of fatty liver and triggering of porphyria cutanea tarda are likely due to estrogenic effects on the liver in the setting of a genetic predisposition to fatty liver disease or porphyria cutanea tarda.