I'd like to comment on myoga's post--in particular her statement "The half life of anastrozole is 50 hours, why do we have to take it everyday? After 100 days we accumulate over 50 pills(?) in our system."
The half-life of a medication is the time it takes for half of the dose to leave the body. Suppose 1 anastrozole pill contains 1 mg. 50 hours after you take the pill, 0.5 mg is still in your body. After another 50 hours 0.25 mg is still in your body. After another 50 hours, 0.125 mg is still in your body--and so on. You take anastrozole every day, because some of it leaves your body every day. So you have to keep replenishing it to keep a constant level.
Generally, it takes about 6 half-lives for a drug to reach a steady state in the body. That steady state level for anastrozole is about 1 mg. You do **not** accumulate 50 pills worth of anastrozole in your system if you take it for 100 days.
Also, even if one AI gives you terrible side effects, a different one may not. There's no way of predicting which (if any) you'll be able to tolerate. You just have to try each one and see. Is this a good situation? I'd say "no" but right now AIs (and tamoxifen) are all we've got. A better med (Giredestrant) is in the pipeline but (as far as I know) not yet available except in a research setting.
@ecwilmot Thank you so much for sharing. I just started and taking half a pill daily right now, but thinking of taking one pill every other day. It's still less than recommended, but fewer side effects, so I'm okay so far. I had terrible side effects with the other two. Gentle is best for me.
@brightlight66 I tried 1/2 pill each day and still had terrible side effects. The one full pill every other day is very tolerable for me. Everyone's journey is so different but know that there is a huge community of women rooting for you!
@ecwilmot
I’m taking letrozole, now in 7th month pre/lumpectomy surgery in March. But the tiredness is getting to me, along with overall fatigue and anxiety knowing this is going to be a long time (5-10 years post surgery). Further, I have had this breast lump over two years but was told “nothing to worry about”—until it WAS . So angry with the medical staff I went to during all this as it was not diagnosed until I saw a gynecologist who pursued the lump then my life was in a tailspin with numerous tests and biopsies. Was told “mastectomy” but switched to oncologist who said I could take the letrozole 6-9 months then have lumpectomy. Now being told if pathology report requires more “removal “, it could still result in a mastectomy. So I am continuing to take the letrozole until 9 month mark in hopes tumor will continue to shrink and lumpectomy will suffice. I’m going to be hugely disappointed if it becomes a more aggressive surgery and an ensuing mastectomy is needed. Anyone else have similar experience? And any side effects from the letrozole? Dreading the thought of having to take it for several years… Maybe the every-other-day would help (?) and will be asking about that—or just taking my chances w/o any drugs since I’m turning 79 soon.
@buckokey Oh, it is all so scary and difficult. Just know that there is a huge community of women who are rooting for you and sending you love. I will hold you in my heart as you make this journey.
@brightlight66 I tried 1/2 pill each day and still had terrible side effects. The one full pill every other day is very tolerable for me. Everyone's journey is so different but know that there is a huge community of women rooting for you!
I'd like to comment on myoga's post--in particular her statement "The half life of anastrozole is 50 hours, why do we have to take it everyday? After 100 days we accumulate over 50 pills(?) in our system."
The half-life of a medication is the time it takes for half of the dose to leave the body. Suppose 1 anastrozole pill contains 1 mg. 50 hours after you take the pill, 0.5 mg is still in your body. After another 50 hours 0.25 mg is still in your body. After another 50 hours, 0.125 mg is still in your body--and so on. You take anastrozole every day, because some of it leaves your body every day. So you have to keep replenishing it to keep a constant level.
Generally, it takes about 6 half-lives for a drug to reach a steady state in the body. That steady state level for anastrozole is about 1 mg. You do **not** accumulate 50 pills worth of anastrozole in your system if you take it for 100 days.
Also, even if one AI gives you terrible side effects, a different one may not. There's no way of predicting which (if any) you'll be able to tolerate. You just have to try each one and see. Is this a good situation? I'd say "no" but right now AIs (and tamoxifen) are all we've got. A better med (Giredestrant) is in the pipeline but (as far as I know) not yet available except in a research setting.
@peggydobbs
I agree! The reason I put 50 with a question mark because I know it’s not 50. To calculate the exact amount of the accumulated drug in your body you need to have a mathematical equation which I don’t remember since I’ve been out of college for over 40 years. I can always research to find out the exact amount. But that’s not my point! My point is that if the half life is 50 hours, then we are accumulating more medication in our body than we need to lower estrogen. The amount of medication we need depending on our body weight and it shouldn’t be one size fits all or it seems like we’re overdosed! That explains the links you posted regarding lower doses being non inferior to standard doses for AIs. By the way, taking it everyday is not keeping “constant level”, you actually accumulate as time goes on because half life is 50 hours. So the first day is 1mg, the next day would be 1mg+1mg(1-24/100) and so on, right?
I came across the article regarding the lower dose for exemestane about a year ago. Exemestane half life is 24 hours, yet taking it 3 times a week is non inferior to standard one a day. That could mean the amount of drug in one pill is more than what we need if taking daily.
I’m not advocating or encouraging lower doses, but if your body can’t handle the full dose, then you need to discuss with your doctor if lower dose is right for you. Would it be better to take lower dose than not to take it at all. Then again if I get to 70s, I would be more interested in living the rest of my life pain free. It’s a personal choice and I respect that. As far as I’m concerned we are here to support our sisters, not judging them.
After two years, three months on anastrozole 1 mg, I just started every other day. I have the common hot flashes, aches, joint pain and tired feeling. I will post again in a few weeks. I was fortunate that my cancer was small. It was estrogen related after years on HRT (over 20 years). Had ten rounds of radiation within 5 days after surgery. Presently 77 years old and 110 lbs, so maybe the 1 mg is too much for me. I am thinking it is better than stopping.
Thank you all for posting and sharing!
To myoga: 1) you are correct that taking 1mg pill of exemestane every other day lowers estrogen the same amount as taking 1 mg daily. However, what the exemestane study does not show (because that wasn't studied) is whether tumor recurrence is the same on the lower dose. It might be--or it might not be.
2) The half-life formula could be interpreted to say that no medication is ever completely eliminated from the body--because of half of half of half ad infinitum never gets to zero. That would mean that a (very) small amount of medication I took as a tiny baby is still in my system. It would be interesting to know if that's true.
Just popping in here to say I switched from Anastrazole to Letrozole after about 1.5 years. Now approaching 3 years (so 1.5 on leteozole) and my symptoms are very much improved. No longer have broken feet/difficulties walking in the am (or often after sitting), hot flashes lessened but not gone, sleep much improved (I was swapping sleep meds/magnesium/advice pm etc in an effort to combat and tend to think I then had sleep anxiety just dreading the night to come). Anyways-it is tru diff meds effect people differently so worth a try IMO. I cannot speak to the every-other-day pill although it sounds enticing. My MD was adamant that the 1 MG was studied to be the lowest/most efficiently effective long term but I have heard people trying this. I fully understand how the side effects become too much and you start to weigh alternatives and "what would you rather thoughts.
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I'd like to comment on myoga's post--in particular her statement "The half life of anastrozole is 50 hours, why do we have to take it everyday? After 100 days we accumulate over 50 pills(?) in our system."
The half-life of a medication is the time it takes for half of the dose to leave the body. Suppose 1 anastrozole pill contains 1 mg. 50 hours after you take the pill, 0.5 mg is still in your body. After another 50 hours 0.25 mg is still in your body. After another 50 hours, 0.125 mg is still in your body--and so on. You take anastrozole every day, because some of it leaves your body every day. So you have to keep replenishing it to keep a constant level.
Generally, it takes about 6 half-lives for a drug to reach a steady state in the body. That steady state level for anastrozole is about 1 mg. You do **not** accumulate 50 pills worth of anastrozole in your system if you take it for 100 days.
Also, even if one AI gives you terrible side effects, a different one may not. There's no way of predicting which (if any) you'll be able to tolerate. You just have to try each one and see. Is this a good situation? I'd say "no" but right now AIs (and tamoxifen) are all we've got. A better med (Giredestrant) is in the pipeline but (as far as I know) not yet available except in a research setting.
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2 Reactions@brightlight66 I tried 1/2 pill each day and still had terrible side effects. The one full pill every other day is very tolerable for me. Everyone's journey is so different but know that there is a huge community of women rooting for you!
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3 Reactions@buckokey Oh, it is all so scary and difficult. Just know that there is a huge community of women who are rooting for you and sending you love. I will hold you in my heart as you make this journey.
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1 Reaction@ecwilmot Thank you so much for sharing your experience. I started the one pill every other day TODAY to see how it goes. Hugs to you!
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1 Reaction@peggydobbs
I agree! The reason I put 50 with a question mark because I know it’s not 50. To calculate the exact amount of the accumulated drug in your body you need to have a mathematical equation which I don’t remember since I’ve been out of college for over 40 years. I can always research to find out the exact amount. But that’s not my point! My point is that if the half life is 50 hours, then we are accumulating more medication in our body than we need to lower estrogen. The amount of medication we need depending on our body weight and it shouldn’t be one size fits all or it seems like we’re overdosed! That explains the links you posted regarding lower doses being non inferior to standard doses for AIs. By the way, taking it everyday is not keeping “constant level”, you actually accumulate as time goes on because half life is 50 hours. So the first day is 1mg, the next day would be 1mg+1mg(1-24/100) and so on, right?
I came across the article regarding the lower dose for exemestane about a year ago. Exemestane half life is 24 hours, yet taking it 3 times a week is non inferior to standard one a day. That could mean the amount of drug in one pill is more than what we need if taking daily.
I’m not advocating or encouraging lower doses, but if your body can’t handle the full dose, then you need to discuss with your doctor if lower dose is right for you. Would it be better to take lower dose than not to take it at all. Then again if I get to 70s, I would be more interested in living the rest of my life pain free. It’s a personal choice and I respect that. As far as I’m concerned we are here to support our sisters, not judging them.
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6 ReactionsAfter two years, three months on anastrozole 1 mg, I just started every other day. I have the common hot flashes, aches, joint pain and tired feeling. I will post again in a few weeks. I was fortunate that my cancer was small. It was estrogen related after years on HRT (over 20 years). Had ten rounds of radiation within 5 days after surgery. Presently 77 years old and 110 lbs, so maybe the 1 mg is too much for me. I am thinking it is better than stopping.
Thank you all for posting and sharing!
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Hug
6 ReactionsTo myoga: 1) you are correct that taking 1mg pill of exemestane every other day lowers estrogen the same amount as taking 1 mg daily. However, what the exemestane study does not show (because that wasn't studied) is whether tumor recurrence is the same on the lower dose. It might be--or it might not be.
2) The half-life formula could be interpreted to say that no medication is ever completely eliminated from the body--because of half of half of half ad infinitum never gets to zero. That would mean that a (very) small amount of medication I took as a tiny baby is still in my system. It would be interesting to know if that's true.
Just popping in here to say I switched from Anastrazole to Letrozole after about 1.5 years. Now approaching 3 years (so 1.5 on leteozole) and my symptoms are very much improved. No longer have broken feet/difficulties walking in the am (or often after sitting), hot flashes lessened but not gone, sleep much improved (I was swapping sleep meds/magnesium/advice pm etc in an effort to combat and tend to think I then had sleep anxiety just dreading the night to come). Anyways-it is tru diff meds effect people differently so worth a try IMO. I cannot speak to the every-other-day pill although it sounds enticing. My MD was adamant that the 1 MG was studied to be the lowest/most efficiently effective long term but I have heard people trying this. I fully understand how the side effects become too much and you start to weigh alternatives and "what would you rather thoughts.
Sending ❤️ to all on this journey.
-laurie
58 ILC lump x2 and radiation
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