The active ingredient exemestane is a so-called aromatase inhibitor and prevents the body’s production of estrogens. The inhibition of hormone production is particularly indicated in women with advanced breast cancer when the growth of the tumor is hormonally influenced. Here you can read everything you need to know about the exemestane structure, usage, exemestane side effects, and interactions.
A Guide to How the Exemestane Structure Works
Estrogens (estrone, estradiol, and estriol) are female sex hormones. They are formed in the female body (in small quantities also in the male) from precursors, especially in the ovaries. The sex hormones are important for the development of sexual characteristics. Then afterward, together with other hormones (such as progesterone), keep the menstrual cycle going. During the menopause, the ovaries gradually stop producing estrogen. After that, the hormone is only produced in small amounts in other tissues (muscles, fat tissue, and mammary gland tissue). So the estrogen level drops to very low levels.
Is Exemestane a Steroid?
The research chemical Exemestane is also known as the brand name Aromasin. The substance is used to treat breast cancer. Exemestane is classed as a steroid because it is structurally comparable to 4-androstenedione, a natural substance of Aromata.
In some cases of breast cancer, the tumor is hormone-sensitive, meaning that its growth depends on estrogen. The low estrogen level after the menopause may be sufficient for this. To suppress this hormone-controlled tumor growth, aromatase inhibitors such as exemestane are used. They inhibit the enzyme aromatase in muscle and fat cells, which is involved in the conversion of estrogen precursors into active hormones. This drastically lowers the estrogen level, which can often prevent further tumor growth.
Absorption, Breakdown, and Excretion of Exemestane
After ingestion, the active ingredient is absorbed into the blood via the intestinal mucosa and first transported to the liver. Most of it is mined there. The rest (less than ten percent) goes into muscle and fat tissue, where it blocks aromatase. Exemestane is broken down in the liver and excreted in urine and stool.
When is Exemestane Used?
- The aromatase inhibitor exemestane is approved for the supportive treatment of hormone-sensitive, early breast cancer after two to three years of treatment with the active ingredient tamoxifen.
- The drug is also approved for the treatment of advanced breast cancer if the tumor growth could not be stopped with tamoxifen.
- Only postmenopausal women may be treated with exemestane; however, this can also be brought about prematurely with the help of medication.
- In order to prevent tumor growth in the long term, the active ingredient is usually taken over several years.
An Example of an Exemestane Dosage Used:
The active substance exemestane is taken as a tablet once a day, after a meal, as this improves absorption. The usual daily dose is 25 milligrams of exemestane. The duration of use in patients with early breast cancer is determined individually by the doctor, in advanced breast cancer, the therapy is usually permanent as long as the tumor does not continue to grow.
What are the side effects of exemestane? Since there is a sudden, sharp drop in estrogen levels with exemestane, severe post-menopausal symptoms can occur, especially at the start of therapy.
- Exemestane side effects such as headache, drowsiness, depression, insomnia, decreased white blood cells, hot flashes, abdominal pain, nausea, increased blood and liver enzyme levels, sweating, exhaustion, and muscle and joint pain occur in more than one in ten treated women.
- Other common side effects include loss of appetite, reduced platelet count, abnormal sensations, vomiting, diarrhea, constipation, indigestion, hair loss, rash, itching, broken bones and decreasing bone density, as well as water retention and weakness.
The combination of Exemestane and alcohol in small amounts is not thought to affect the treatment or cause any harm. It is also important to mention to any doctor or dentist if you are taking this medication.