One Size Fits All Aromatase Inhibitor????

[Donna]

Hi Amazing Group,

I am just wondering - it seems obvious to me that heavier people using an AI would need a larger dosage since fat is one of the culprits that helps create estrogen - at least that is what I am given to understand.

Do I have this right - and if so, why wouldn't heavier people need a larger dosage AI than slimmer trimmer folk?

Pondering away in sunny California - Donna

[michka]

Donna, this is a very good question.
I had a lot of trouble supporting Arimidex and now Aromasin. My onc cut the Aromasin to one every two days. I asked him if it would still be working and if there were rules about dosages. He said that no study had been done on that. He added that once the medecine is out, the labs do not really care about the side effects and the rest. That's nice! I don't feel comfortable
It is true that our weight should also count, no?
Michka

[PinkGirl]

This is a good question Donna. The way I understand it, aromatase is an enzyme that changes androgens into
estrogen, and the androgens are in our body fat.
I don't know if having more fat means more androgens.

If this is the case, I would definitely need to double up
on my arimidex!!!

[Becky]

The original Arimidex trials used 1mg (the dose we all take) vs 10mg and there was absolutely no difference in effectiveness.

Alittle goes a long way. I am not sure if they ever tested less than 1mg.

[PinkGirl]

Hey Becky
Do you know if having more body fat means having
more adrogens that get changed to estrogen???

[Becky]

Assuming no aromatase inhibitors - yes, it is factual that being postmenopausal being overweight equals more circulating estrogen. This is why being overweight increases your risk of bc (but primarily hormone positive type). More hormones to stimulate hormone positive atypical cells to make the next step.

[Donna]

Dear Becky,

I know I can always count on you for great information, you really know your stuff! I realized that most of these tests refer to so many milligrams per kilogram, so I had wondered how they arrived at the dosage prescribed.

Thanks so much for your clear, concise, easy to understand answers!

Have a great day!

Donna

[sarah]

Great question!
sarah

[harrie]

I would sure like to cut mine down to one tab every other day.

That is a very logical question Donna.

[Becky]

Changing the dose of your AI should only be done under the care of your onc. Unlike Tamoxifen, AIs do not last long in the body and should be taken every day. At first, it takes up to 3 weeks for the AI to really be 100% effective (in inhibiting the action of aromatase).

Tamoxifen, however, takes about 3-4 weeks to be eliminated from the body.

[Jackie07]

I am no expert. But I just thought about one thing. I think we all have pretty much the same amount of blood circulating our body no matter how thin or heavy we are.
What I mean is, even when one's weight is twice of mine, she won't have twice amount of the blood. In that sense, the dose probably is not necessarily to be doubled or in direct proportion to our weight. That's probably why they needed trial to see what the most effective and effecient dosage is.

[CLTann]

Hi,

I was having bone density loss, although I have been, off and on, taking Fosamaz weekly. I asked my onc today why do I ( small frame and lean) need to take the same dosage of Femera as a big woman does. He said it is the enzyme in the body that the A.I. trying to counteract. Since no one can gauge the amount of enzyme, the dosage has been set at a standard amount for everyone. There is no data to support the efficacy at a lower dosage or less frequency. As to the bone loss, he asked me to do the best in getting tolerance with biphosphate. Another bone density specialist is recommended.

[harrie]

Ann, thanks for the info on the AI.
In regards to the biophosphonate and the bone loss, it helps to supplement with Vit D3.