Femara Letrozole Anti Estrogen 112809-51-5 Infertility Breast Cancer Treatment
Letrozole Details:
Product name:Letrazole,Femara
Synonyms:4,4'-(1h-1,2,4-Triazol-1-Ylmethylene)Bisbenzonitrile; Lelrozol; 4,4'-(1h-1,2,4-Triazol-1-Ylmethylene) Bis-Benzonitrile;Letrozol; Femara
CAS:112809-51-5
Molecular Formula:C17H11N5
Molecular Weight :285.31
Melting point:181-183ºC
Appearance: Off-white crystalline powder
Assay:99.5%
Shipment: EMS, DHL, FedEx.ect.
Letrozole Description:
Letrozole(Femara) was first developed in an effort to combat breast cancer in post-menopausal women. In fact, it would prove to be virtually identical to the already popular AI in Arimidex (Anastrozole). While intended for breast cancer treatment, like many AI’s, it has found a welcomed home among anabolic steroid users. Letrozole is one of the most commonly used anti-estrogens among steroid users duringsteroid use to combat possible estrogenic related side effects. It is so effective as an anti-estrogen in this regard many anabolic steroidshave effectively reversed gynecomastia symptoms with Letrozole.
Letrazole(Femara) is used to treat certain types of breast cancer (such as hormone-receptor-positive breast cancer) in women after menopause. Letrozole is also used to help prevent the cancer from returning. Some breast cancers are made to grow faster by a natural hormone called estrogen. Letrozole decreases the amount of estrogen the body makes and helps to slow or reverse the growth of these breast cancers.This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.
How Letrozole Works:
Letrozole lowers the levels of the female sex hormone oestrogen in the body. Oestrogen stimulates some breast cancers to grow. These breast cancers are called hormone sensitive or hormone receptor positive. Letrozole can stop or slow the growth of these cancers. It can also reduce the chance of a breast cancer coming back after surgery.
Letrozole only works in women who have had their menopause. It is a type of drug called an aromatase inhibitor. After the menopause, women don’t produce oestrogen from their ovaries. But they still produce a small amount by using an enzyme called aromatase which turns other sex hormones called androgens into oestrogen. This change happens mainly in fatty tissue, muscle and the skin. Aromatase inhibitors block aromatase so that it can’t change the androgen into oestrogen.
Effects of Letrozole:
Letrozole as an anti-estrogen is extremely beneficial to breast cancer patients. Many forms of breast cancer actively feed off the estrogen hormone. By inhibiting the production of estrogen, which in turn lowers the amount of circulating estrogen in the body, this has the ability to starve the cancer. For years Nolvadex was the preferred form of treatment for this purpose. Nolvadex actively binds to the estrogen receptor, thereby preventing estrogen from binding. However, it does not inhibit or lower production. Nolvadex is still extremely valuable in breast cancer treatment plans, but many physicians, especially in extreme cases have begun to use AI’s first. Once the cancer is in remission, at this stage a SERM like Nolvadex may replace the AI in an effort to protect against the cancer reappearing.
Undeniably, AI’s like Letrozole are the most effect means at combating estrogenic related side effects. However, they can also have a negative impact on cholesterol. Alone AI’s do not appear to have a strong, negative effect on cholesterol, but when coupled with an aromatizing steroid like testosterone the adverse cholesterol effect is enhanced. For this reason, many will find SERM’s like Tamoxifen Citrate (Nolvadex) should be their first choice in estrogen protection. SERM’s will not negatively affect cholesterol; in fact, SERM’s, while anti-estrogenic, actively act as estrogens in the liver, and in turn, promote healthier cholesterol levels. We’ll look at this in more detail in the side effect section, and while Letrozole can be used without an adverse cholesterol effect, it will take some effort on your part.
Important Points to Remember:
Talk to your doctor, pharmacist or nurse about all your side effects so they can help you manage them. They can give you advice or reassure you. Your nurse will give you a contact number to ring if you have any questions or problems. If in doubt, call them.
Other medicines
Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and over the counter remedies. Some drugs can react together.
Pregnancy and contraception
This drug may harm a baby developing in the womb. It is important not to become pregnant while you are having treatment and for a few months afterwards. Even if you have had your menopause, talk to your doctor or nurse about effective contraception before starting treatment.
Femara and Letrozole Dosing:
The most common dose of Femara is 2.5 mg per day on days five through nine of the menstrual cycleSometimes it is given in higher doses of 5 mg or 7.5 mg per day.
Letrozole COA:
Tests | Specifications | Results |
Appearance | White or off-white crystaline powder | White Crystalline powder |
Solubility | Soluble in Chloroform; Soluble in ethanol when heated | Conform |
ldentification | (1)Maximum absorption in wavelength of 240 nm Minimum absorption in wavelength of 215 nm | Conform Conform |
(2)Infrared spectrum should be in accordance the dominant peak of contrast | In accordance with the dominant peak of contrast | |
Melting points | 182℃-184℃ | 182℃ |
Related substances | <0.5% | 0.3% |
Single impurity | <0.3% | 0.2% |
Loss on drying | <1.0% | 0.8% |
[Assay]C17H11N5 (On anhydrous basis) | >98.0% | 99.2% |
Conclusion | Conforms Specifications of USP35 |