Aromatase Inhibitors List: Essential Tools in Cancer Hormone Therapy
Aromatase inhibitors are a type of hormone therapy for breast cancer. Here’s our list comparing anastrozole, exemestane, and letrozole.
anastrozole
Used for Breast Cancer
Used for Breast Cancer
Anastrozole (Arimidex) is prescription oral medication used to treat certain types of breast cancer, including both early and advanced or metastatic stages. It's FDA approved only for postmenopausal women, or those who have already gone through menopause. This medication belongs to a class called aromatase inhibitors, which works by lowering estrogen levels in the body. You take one tablet by mouth once a day, with or without food. Common side effects include hot flashes, weakness, and joint pain.
What is Anastrozole (Arimidex)?
What is Anastrozole (Arimidex) used for?
- Early breast cancer (HR+) in postmenopausal women
- Advanced or metastatic breast cancer HR+ or HR unknown in postmenopausal women
- Advanced breast cancer in postmenopausal women whose cancer has worsened after treatment with tamoxifen
How Anastrozole (Arimidex) works
Anastrozole (Arimidex) is an aromatase inhibitor, meaning it blocks a protein in your body called aromatase. Aromatase helps make estrogen, a hormone that can cause some types of breast cancer to grow.
By blocking aromatase, anastrozole (Arimidex) lowers estrogen levels in your body. This helps slow down or stop the growth of breast cancer that depends on estrogen to grow.
When does Anastrozole (Arimidex) start working?Time passed since treatment started:
Drug facts
| Common Brands | Arimidex |
|---|---|
| Drug Class | Aromatase inhibitor |
| Controlled Substance Classification | Not a controlled medication |
| Generic Status | Lower-cost generic available |
| Availability | Prescription only |
More on Anastrozole (Arimidex) essentials
Side effects of Anastrozole (Arimidex)
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Common Side Effects
Early breast cancer:
- Hot flashes (36%)
- Muscle and joint problems (36%)
- Tiredness (19%)
- Changes in mood (19%)
- Nausea and vomiting (13%)
- Bone fractures (10%)
Advanced or metastatic breast cancer:
- Nausea and vomiting (34%)
- Hot flashes (26%)
Advanced breast cancer that's worsened after tamoxifen treatment:
- Nausea and vomiting (29%)
- Hot flashes (13%)
Less Common Side Effects
Early breast cancer:
- Cataracts
- Vaginal bleeding
- Vaginal discharge
Advanced or metastatic breast cancer:
- Depression
- Vaginal dryness
- Vaginal bleeding
- Tiredness
- Weight gain
Advanced breast cancer that's worsened after tamoxifen treatment:
- Swelling in the arms and legs
- Vaginal dryness
- Weight gain
Anastrozole (Arimidex) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Heart disease: chest pain, shortness of breath, lightheadedness
When do Anastrozole (Arimidex) possible side effects begin and end?
Time passed since treatment started:
M
H
D
W
M
Hot flashes
Muscle and joint problems
Nausea and vomiting
Tiredness
Changes in mood
If a line continues to the right, you'll likely keep experiencing this side effect once it starts.
More on Anastrozole (Arimidex) side effects
The following Anastrozole (Arimidex) 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:
More common
Blurred vision
bone pain
chest pain or discomfort
dizziness
headache
nervousness
pounding in the ears
slow or fast heartbeat
swelling of the feet or lower legs
Less common
Arm, back, or jaw pain
chest tightness or heaviness
chills
cough producing mucus
difficult or painful urination
difficulty breathing
dizziness, severe
headache, continuing
hoarseness
increased blood pressure
lower back or side pain
pain, tenderness, bluish color, or swelling of the foot or leg
sweating
unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
vaginal bleeding (unexpected and heavy)
Incidence not known
Blistering, peeling, or loosening of the skin
confusion
dark urine
difficulty swallowing
general tiredness and weakness
hives or welts, itching, skin rash
incoherent speech
increased urination
joint or muscle pain
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
light-colored stools
loss of appetite
metallic taste
muscle weakness
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
red skin lesions, often with a purple center
red, irritated eyes
sores, ulcers, or white spots in the mouth or on the lips
stomach pain
thirst
upper right abdominal pain
vomiting
yellow eyes and 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
congestion
decrease in height
feeling of warmth
flushing or redness of the skin, especially on the face and neck
increased appetite
indigestion
lack or loss of strength
mood or mental changes
pain in the back, ribs, arms, or legs
pain, general
pelvic pain
stomach discomfort or upset
tender, swollen glands in the neck
trouble in swallowing
voice changes
Less common
breast pain
dryness of the vagina
general feeling of discomfort or illness
joint stiffness
loss of hair
numbness or tingling of the hands or feet
shivering
sleepiness
trouble sleeping
Incidence not known
Difficulty in moving
muscle cramps or stiffness
swollen joints
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.
Get your GoodRx coupon
$89.40
GoodRx discount
$10.06
Pros and cons of Anastrozole (Arimidex)
Pros
- Oral tablet taken once a day
- Can be taken with or without food
- Helps reduce the risk of breast cancer coming back
Cons
- Only FDA approved to treat postmenopausal women
- Commonly causes hot flashes, joint pain, weakness
- Typically need to take it for at least 5 years
Pharmacist tips for Anastrozole (Arimidex)
- Take anastrozole (Arimidex) once a day with or without food. Try to take it at the same time each day to help you remember.
- If you miss a dose of anastrozole (Arimidex), take it as soon as you remember. If it’s almost time for your next dose, skip the missed one and take your regular dose. Don’t take two doses at once.
- Anastrozole (Arimidex) can weaken your bones, making them more prone to fractures. Your oncologist might recommend that you take calcium or vitamin D to strengthen your bones.
- Anastrozole (Arimidex) might raise cholesterol levels, which can raise your risk for serious heart disease. Your oncologist might order regular blood tests to make sure your cholesterol stays in a healthy range.
- Inform patients of the possibility of serious allergic reactions with swelling of the face, lips, tongue and/or throat (angioedema) which may cause difficulty in swallowing and/or breathing and to seek medical attention immediately.
- If you notice tingling, numbness, or a tickling feeling while taking anastrozole (Arimidex), contact your care team right away. These could be side effects that need attention.
- Avoid taking any medications that contain estrogen while taking anastrozole (Arimidex). Since this medication works to lower estrogen levels, adding more estrogen can make it not work as well.
- If you can become pregnant, use birth control while taking anastrozole (Arimidex) and for at least 3 weeks after your last dose. Contact your oncologist right away if you become pregnant or think you might be pregnant during treatment.
Risks and warnings for Anastrozole (Arimidex)
Anastrozole (Arimidex) 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 disease
- Risk factors: History blocked heart arteries
Anastrozole (Arimidex) can raise your risk of heart disease, especially if you've had blocked heart arteries in the past. Your oncologist will consider the risks and benefits before deciding if this medication is right for you. Get medical help right away if you start to have chest pain or feel out of breath while taking anastrozole (Arimidex).
Bone loss
Over time, anastrozole (Arimidex) can weaken your bones, which raises your risk for fractures, especially in your spine, hip, or wrist. This happens because the medication lowers estrogen levels, and estrogen plays an important role in keeping bones strong.
Your oncologist might recommend bone mineral density (BMD) testing before and during your treatment to make sure your bones stay healthy. These tests help monitor the strength and thickness of your bones. Your oncologist might also suggest you take calcium or vitamin D to help keep your bones strong during treatment.
Rise in cholesterol levels
Some people who take anastrozole (Arimidex) can develop a rise in cholesterol levels. Having too much cholesterol in your blood can clog your blood vessels and raise your risk of heart attack or stroke. Your oncologist might order regular blood tests to check your cholesterol while you’re taking this medication.
Harm to unborn baby
Anastrozole (Arimidex) can be harmful to an unborn baby. While most people taking this medication have already gone through menopause, some oncologists may prescribe it off-label for women who haven’t. If there’s any chance you could still become pregnant, use birth control while taking anastrozole (Arimidex) and for at least 3 weeks after your last dose to prevent pregnancy.
Anastrozole (Arimidex) dosage
The average cost for 12 tablets of 1mg of Anastrozole (Arimidex) is $10.06 with a free GoodRx coupon. This is 88.75% off the average retail price of $89.40. 
Tablet
Tablet| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 1mg | 12 tablets | $10.06 | $0.84 |
Typical dosage for Anastrozole (Arimidex)
The typical dose is 1 mg by mouth daily.
Interactions between Anastrozole (Arimidex) and other drugs
Anastrozole (Arimidex) may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Anastrozole (Arimidex). Please note that only the generic name of each medication is listed below.
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. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
How much does Anastrozole (Arimidex) cost?
To access savings, use a GoodRx coupon and pay just a fraction of the retail price.
What are alternatives to Anastrozole (Arimidex)?
There are a number of medications that your doctor can prescribe in place of Anastrozole (Arimidex). Compare a few possible alternatives below.
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Anastrozole (Arimidex) images
