I have been on Arimidex for 3 years. When I first started the drug, I experienced a lot of side effects and questioned my oncologist extensively. He insisted that the side effects would dissipate, and within 4-6 months, they did.
But at the beginning I had trouble sleeping, had hot flashes, but most of all had severe muscle and joint pain. It was to the point where I couldn’t walk without incredible pain, and at one point I lost the feeling in my right arm. (I actually went to the ER and they thought I was having a heart attack!) I did a lot of reading, and many women had the same side effects as I did.
Here is some information about Arimidex as provided by BreastCancer.org:
Arimidex (chemical name: anastrozole) is an aromatase inhibitor approved by the U.S. Food and Drug Administration (FDA) to treat:
• postmenopausal women diagnosed with hormone-receptor-positive, early-stage breast cancer after surgery (or possibly chemotherapy and radiation) to reduce the risk of the cancer coming back
• postmenopausal women diagnosed with advanced-stage or metastatic hormone-receptor-positive breast cancer
Arimidex won’t work on hormone-receptor-negative breast cancer. Arimidex shouldn’t be taken at the same time as tamoxifen.
Arimidex is a pill taken once a day. Most doctors recommend taking Arimidex at the same time each day.
Benefits of Arimidex
Since 1999, researchers have been conducting the large ATAC (Arimidex, Tamoxifen Alone or in Combination) trial to compare Arimidex to tamoxifen after surgery. The researchers are looking at how the medicines work by themselves as well as together to see which combination is the best treatment for postmenopausal women diagnosed with early-stage, hormone-receptor-positive breast cancer. Based on initial results of this trial, giving Arimidex and tamoxifen at the same time isn’t recommended.
So far, the results show that 5 years of Arimidex is better than 5 years of tamoxifen as the first hormonal therapy for postmenopausal women with early-stage, hormone-receptor-positive breast cancer. Arimidex is better than tamoxifen for:
• increasing the time before the cancer comes back in those who experience recurrence
• reducing the risk of the cancer spreading to other parts of the body
• reducing the risk of a new cancer developing in the other breast
Side effects of Arimidex
Because Arimidex lowers the amount of estrogen in the body, less estrogen reaches bone cells, which can lead to bone thinning and weakening and a higher-than-average risk of broken bones. This side effect can be very troubling for some women. If you have osteoporosis, your doctor may recommend that you take tamoxifen rather than Arimidex because of this possible side effect.
Still, the ATAC results reported in 2007 showed a finding that hadn’t been seen before. The higher risk of broken bones associated with Arimidex disappeared after the women stopped taking Arimidex. The researchers will see if this result continues as more data is collected and analyzed.
Other common side effects of Arimidex are bone and joint pain, nausea, vomiting, hot flashes, weakness and fatigue.
Joint pain from taking Arimidex can be troubling. But a 2008 British study suggests that women who experienced joint pain 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 women stick with treatment despite the side effects.
Some women may have other side effects while taking Arimidex:
• headache
• loss of appetite
• constipation
• diarrhea
• heartburn
• weight gain
• mood changes
• difficulty sleeping
• dizziness
• vaginal bleeding
• vaginal dryness
• dry mouth
• dry skin
• cough
• hair changes
How long do you take Arimidex?
In most cases, you’ll take Arimidex for 5 years. Doctors may recommend that some women take it for a longer or shorter period of time.
Please share your story about how Arimidex effected you and if you had any side effects and for how long?
