1. < Breast Cancer
Profile picture for wews

Letrozole side effects and timing?

Posted by wews @wews, Aug 22, 2025

Could those of you you are taking or have taken letrozole share when side effects started to appear? I have been taking it since April 2025 and within the last month I am losing hair, feel some stomach and intestine discomfort and some joint and low back pain. I work out and do yoga and breathing which helps the joint and back but has anyone else noticed their hair falling out or thinning? Also do these side effects go away after a bit or do they get worse over time? What are your experiences? I have to stay on this for a long time and would love to prepare myself. Thanks.

Interested in more discussions like this? Go to the Breast Cancer Support Group.

Profile picture for teacher22
teacher22 | @teacher22 | Jan 2 2:48pm
In reply to @wews "@teacher22 thanks for your insight. How often does your oncologist check your liver? While I have..." + (show)
Profile picture for wews @wews

@teacher22 thanks for your insight. How often does your oncologist check your liver? While I have had blood work done since I started letrozole in April it hasn’t been ordered by my oncologist.

Jump to this post

@wews
I was referred to a hepatologist. When I had high liver enzymes I was getting them checked every two weeks. Then it was once a month and then three months. Because they have been at normal levels or only slightly elevated, I just get them checked when my hematologist does a complete metabolic panel around every six months.

REPLY
1 reply
Profile picture for wews
wews | @wews | Jan 3 6:49am
In reply to @teacher22 "@wews I was referred to a hepatologist. When I had high liver enzymes I was getting..." + (show)
Profile picture for teacher22 @teacher22

@wews
I was referred to a hepatologist. When I had high liver enzymes I was getting them checked every two weeks. Then it was once a month and then three months. Because they have been at normal levels or only slightly elevated, I just get them checked when my hematologist does a complete metabolic panel around every six months.

Jump to this post

@teacher22 thanks much for your insights

REPLY
Profile picture for lifetraveler
lifetraveler | @lifetraveler | Jan 3 6:56am
In reply to @wews "@teacher22 thanks for your insight. How often does your oncologist check your liver? While I have..." + (show)
Profile picture for wews @wews

@teacher22 thanks for your insight. How often does your oncologist check your liver? While I have had blood work done since I started letrozole in April it hasn’t been ordered by my oncologist.

Jump to this post

@wews :

Just to offer my 2cents based on my personal experience...
My medical oncologist ordered quarterly COMPREHENSIVE METABOLIC PANEL and CBC W/ AUTO DIFFERENTIAL blood work done for me to make sure that all the elements are in normal range ever since I started taking Anarzole 2 years ago. COMPREHENSIVE METABOLIC PANEL checks including key liver enzymes such as: ALT, AST, measured in blood tests.

Best wishes to you all on the journey ahead and Happy New Year!

REPLY
1 reply
Profile picture for wews
wews | @wews | Jan 3 8:11am
In reply to @lifetraveler "@wews : Just to offer my 2cents based on my personal experience... My medical oncologist ordered..." + (show)
Profile picture for lifetraveler @lifetraveler

@wews :

Just to offer my 2cents based on my personal experience...
My medical oncologist ordered quarterly COMPREHENSIVE METABOLIC PANEL and CBC W/ AUTO DIFFERENTIAL blood work done for me to make sure that all the elements are in normal range ever since I started taking Anarzole 2 years ago. COMPREHENSIVE METABOLIC PANEL checks including key liver enzymes such as: ALT, AST, measured in blood tests.

Best wishes to you all on the journey ahead and Happy New Year!

Jump to this post

@lifetraveler thanks so much. I will make a note to make sure I have this done as well.

REPLY
Profile picture for ccc1965
ccc1965 | @ccc1965 | Jan 3 9:05am
In reply to @wews "@teacher22 thanks for your insight. How often does your oncologist check your liver? While I have..." + (show)
Profile picture for wews @wews

@teacher22 thanks for your insight. How often does your oncologist check your liver? While I have had blood work done since I started letrozole in April it hasn’t been ordered by my oncologist.

Jump to this post

@wews My levels were checked by Primary Doctor during a yearly physical. In September of 2025 my blood work (done by Cancer center) were in the normal range they were significantly elevated in December 2025. I switched from Anastrozole (due to emotional side effects) to Letrozole in late November. I have a CT scheduled for tomorrow.

REPLY
Profile picture for waterlilies1899
waterlilies1899 | @waterlilies1899 | Jun 5 9:41am
In reply to @equilla "After chemo I lost all hair. Then the hair started to grow back but kept falling..." + (show)
Profile picture for equilla @equilla

After chemo I lost all hair. Then the hair started to grow back but kept falling out. This continued over my two year history of treatment. I saw a dermatologist this summer and was prescribed minoxidil. The medication is working. The daily amounts of hair on comb and brush are greatly reduced.

Jump to this post

@equilla I lost about 50% of my hair during chemo, but I also used the cold capping. That being said, I saw a video about Humby Organics Blueberry Fields shampoo bar which stated a women going through chemo using the bar had active hair growth during chemo. I started using that after my second chemo treatment. Within about 2 weeks, my hair loss was still active, but it seemed less. Then after about 3-4 weeks I noticed active hair growth while still on chemo. I am still using the shampoo bar while now on Letrozole and my hair loss is minimal. I also use a hair vitamin called Hair Effects which my naturopath has suggested. Everyone's response to medication and products is different, but this has been successful for me. Hope this helped. BTW, I told them I was currently going through chemo and they sent me a complementary shampoo and conditioner bar. It was such a generous act on their part and now they have a grateful and loyal customer. Plus, it makes my hair feel really clean! Best of luck to you!

REPLY
1 reply
Profile picture for wews
wews | @wews | Jun 5 10:20am
In reply to @waterlilies1899 "@equilla I lost about 50% of my hair during chemo, but I also used the cold..." + (show)
Profile picture for waterlilies1899 @waterlilies1899

@equilla I lost about 50% of my hair during chemo, but I also used the cold capping. That being said, I saw a video about Humby Organics Blueberry Fields shampoo bar which stated a women going through chemo using the bar had active hair growth during chemo. I started using that after my second chemo treatment. Within about 2 weeks, my hair loss was still active, but it seemed less. Then after about 3-4 weeks I noticed active hair growth while still on chemo. I am still using the shampoo bar while now on Letrozole and my hair loss is minimal. I also use a hair vitamin called Hair Effects which my naturopath has suggested. Everyone's response to medication and products is different, but this has been successful for me. Hope this helped. BTW, I told them I was currently going through chemo and they sent me a complementary shampoo and conditioner bar. It was such a generous act on their part and now they have a grateful and loyal customer. Plus, it makes my hair feel really clean! Best of luck to you!

Jump to this post

@waterlilies1899 I have been on a year. Initially I had hot flashes and now they happen seldomly. I had some hair shedding. I am using vegamour shampoo and conditioner and serum and my hair is thicker than ever. It is an all natural product which I would highly recommend. I have some joint that ache or get stiff but the more active I am the better. I do yoga and lift weights and walk and ride bikes. Work those bones to keep them strong. Hang in there!

REPLY
Please sign in or register to post a reply.