Tamoxifen and Synthroid (levothyroxine)

Nancy2581

Tamoxifen and Synthroid (levothyroxine)

Nancy2581

Has anybody been on tamoxifen and synthroid for longer than 6 months? I have read that tamoxifen may affect thyroid levels. Has anybody found this to be true?

Thanks

Nancy

pebee

Yes, it is true. I was on Tamoxifen and Synthroid at the same time. I also take Cytamel (T3) as well. I began having the symptoms of low-thyroid and my original clueless endo told me that I was delusional as the blood work was fine. And, that is the problem - your blood work for thyroid will show that everything is fine, however, you will have all of the symptoms.

I found a paper on this site which explained how this happens when you take Tamoxifen and what it means to our body. I fired my endo and my primary care doctor agreed to up my dosage of Synthroid. However, even with the dosage up, I still had symptoms of very low thyroid coupled with the "too much" Synthroid heart palipations. Now, I am off tamoxifen looking at other options.

farmerlucy

Hey Nancy - I've been taking both for two years. I actually reduced my dosage of synthroid (now 137.5cg)and my numbers look good.

Nancy2581

Hi Jill - oh lucky you - taking synthroid too huh? Lol. I just had my levels tested and my TSH came back at .13 and the range is .3 - 3.8. So now I am hyper ha ha. No wonder I had so much energy. My dr. dropped the dosage from 125 to 112 now and I will retest in a few months.

Thanks

Nancy

farmerlucy

Good thing you are hyper. Helps in running away from rattlesnakes!

Gully

Hello ladies,

Count me in on the thyroid issues. I have been on Tamoxifen since Aug 2013 and synthroid for over 20 years On he same dose. Now on my third round of let's just test wait and see. TSH is steadily diving started at 1.9, then .95, now down to .45. Doctors do not seem to understand this

Nancy2581

gully I feel the same will be happening to me. My thyroid levels have never stabilized during the 5 1/2 years of medication. I started out hypo and am now hyper. Now the tamoxifen maybe lowering my TSH like you - I don't know what to think.

LOL Jill I think I was as traumatized from that rattler as the dogs.

Nancy

labelle

My thyroid issues are one of several reasons I've passed on Tamoxifen as I've read about it messing with your thyroid in more than one place, but if you've had radiation, that may be the actual source of some of these issues. My thyroid has been stable for quite awhile but because I've had radiation my endo is back to monitoring me with blood tests every 6 months. Per my radiologist, "photons go where photons go" and the possibility of "scatter" to the thyroid during full breast radiation is very real. Either way, with tamoxifen or rads, if you've had thyroid issues in the past you are probably going to be spending some extra quality time w your endo.

Nancy2581

Thanks labelle - I don't have an endo. My GP has been monitoring me. Ugh now I wonder if I should go see one.

scvmom65

Hi,

I have been on Synthroid for 20 years and stable. When I added in the Tamox, I felt hypo within a few months. My endo did some detective work and found that my tsh was fine, even higher, but my t3's went below normal for some reason. He dropped the synthroid dose and added 5 mcg of cytomel (t3) and it made a huge difference. Then I developed over 20 ovarian cysts on Tamox, so I was forced to quit it and have my ovaries out. That was a year and a half ago and since then I have had 4 thyroid tests and my blood work is the same, stable with the addition of the t3. So for me I dont' know if it was because of Tamox or maybe just menopause. Not sure but if anyone else is having issues, I would recommend you ask you endo to run the full thyoid panel including the free t3 and free t4.

Anna

Nancy2581

thanks Anna for the info.