Conflict of Drugs

[jasper09]

Been on 75mcg Levo since 2008-since starting Anastrozole in Sept 2013 for breast cancer, Hypo symptoms have increased alongside the side effects from the Breast Cancer drug. The worst is the irregular heart Palps. Has anyone had similar experience, if so how do I stop them? Thanks x

[PinkNinja]

I'm sorry to hear you have such a battle on your hands at the moment.

Irregular heart beat and palpitations can be due to not enough thyroid hormone or too much thyroid hormone. 75mcg is quite a small dose so I wouldn't be surprised if this is contributing to your symptoms.

Iron and cortisol are also very important for your body to use thyroid hormones properly. It would be helpful to have blood tests for thyroid (preferably TSH, t4 and t3 but at least the first two), serum iron, ferritin, folate, vitamin b12, vitamin D and cortisol. Depending on your doctor, he may agree to some or all of these tests. Your results need to be well within the reference range with the exception of the Thyroid tests. TSH often needs to be low for a patient on thyroxine to be well and t4 often needs to be near or at the top of the range. If you have any recent thyroid test results it would be helpful to see them. We may be able to determine whether this is the main cause of your symptoms. If you manage to get any or all of the above tested, please post the results on this forum with then reference range and Someone will be able to interpret them for you.

I'm afraid I don't know anything about the cancer drug you mention but I will see if I can find anything useful.

We will try and help you get to the bottom of what is causing your symptoms. This community is very helpful and supportive

Carolyn x

[PinkNinja]

I'm sorry, I haven't found anything that describes an interaction between the two medications except for anecdotal experiences similar to yours. To me this does suggest that, in some people at least, the effects of thyroxine are impacted to some degree by the anastrozole. Some people become hyperthyroid on starting anastrozole which, I believe, may be link to the reduction of oestrogen in the body. Oestrogen binds with thyroxine rendering it unavailable to the body. The more oestrogen, the less available the thyroxine. The less oestrogen there is, the more thyroxine is free and available for use in the body. Palpitations could therefore be caused by the anastrozole and a reduction of thyroxine may be needed.

In your case, I would be wanting to see your thyroid results as 75mcg is quite a small dose (unless you are very small). It may be that you just don't have enough thyroxine for your body's needs. The symptoms of too little thyroxine can be very similar to the symptoms of too much thyroxine, especially where cardiac symptoms are concerned.

Another thing to note is that your vitamin D level is extremely important if you have thyroid disease. It is also very important if you are taking anastrozole as one side effect of the medication is reduced bone density. I strongly advise you get this checked so you can start supplementing with vitamin D3 at an appropriate dose. Vitamin D is also extremely important for your immune system.

I'm sorry I haven't been able to give you a definitive answer and seem to have given you more questions! I hope I have at least given you information that will help you find out what is wrong so you can take action.

Take care and I hope you find the answer to your recovery soon.

Carolyn x

[jasper09 in reply to PinkNinja]

You have no idea how grateful I am for all this helpful information. I have been saying over a year now it must be a link between both drugs. I see my gp this week and I will be taking my phone to show him this thread. Thank you very much, I will post again after I see my gp hopefully with some better news and also a copy of my Thyroid results. My husband just suggested I ask for a referral to a specialist, I wonder if he will? X

[PinkNinja in reply to jasper09]

It's worth a try given that your case is somewhat more complicated due to the breast cancer.

Bear in mind that there is no official contraindication, just what others have experienced and that your GP therefore may not know about this. Most GPs want to help but are often bound by guidelines. A referral may be a good idea.

I also just read that TSH does not change in anastrazole. In some areas TSH is the only thyroid blood test carried out despite the NICE guidelines that state t4 should also be measured. It is likely to be the t4 that gives you the best information, along with t3 if they'll test it, as the free t4 with be what's affected by oestrogen levels.

Incidentally, oestrogen levels rise during pregnancy which increases the amount of thyroglobulin in the blood. This binds with the t4 making it unavailable to the cells. It makes sense that a medication that reduces oestrogen levels would have the opposite effect.

I know some people on here do not have helpful doctors but many do (mine is excellent) so there is always hope.

Good luck with your doctor. Remember to get a printout of your results.

Carolyn x

[jasper09 in reply to PinkNinja]

Thanks again. Can't wait to speak to gp now! X

[jasper09]

That's why I want to ask my gp this week if he will refer me to a specialist, a lot of people on the Thyroid Group UK on FB have seen one and got results. I will try anything to get back to a "normal" life again and not just existing. X

[jasper09]

Thank you for that. I will definitely check on this and see if there are any near me. X

[Clutter in reply to jasper09]

Jasper, it's [e-mail]

[jasper09 in reply to Clutter]

Thank you, I had a reply from Louise, very helpful. X

[jasper09]

Thank you for that. I will ask gp on Tuesday if I can have these other tests. X

[ritz]

YES

I take now 3.5g armour but had a similar reaction when I started anastrozol my bp went up and up. it is intended to stop the production of oestrogen hormone - but in some also seems to interfere with thyroid hormone production/absorption.

I also had a bad reaction to it and tried letrozole and now exmestasane - which, so far, fingers x seems better for me

previously I took 3g of armour.

[jasper09 in reply to ritz]

Hi Ritz, thanks for the info. I have been banging on about the way I feel since starting Anastrozole for 18 months now. I was already on Thyroxine for 5 years with no probs. Then it all went horribly wrong. My gp said yesterday to contact my specialist breast nurse (she helped me with issues with the drugs last Nov) so I will ask about the Letrozole/Exmestesane if it's worth a try I will try anything, apart from coming off them as my gp almost choked when i threatened to! I was told about the possible clash of drugs by this website, and not any if the medical profession as none of them will commit themselves to agreeing with me. I wondered also if the Breast nurse would be allowed to refer me to a Thyroid specialist? I will keep knocking on everyone's door until I get these issues resolved. It's not asking too much, is it? Michele xx

[ritz]

breast cancer consultant specialist nurse and diaetician at hospital all agreed with me that there seemed to be some conflict going on and gp uped armout to 3.5grains

so keep on at them and good luck.

[jasper09 in reply to ritz]

Well, thanks to you mentioning about changing the cancer drug and that it can affect thyroid, I finally got something positive when I rang my specialist breast nurse today! She is getting me an appt with breast surgeon (who the Nurse said has operated on many thyroid patients and will listen hopefully) and maybe he will change me to Arimidex (didn't realise it's the real version of Anastrozole) or put me on Exemestane, I mentioned you said it seems better for you so far. Anyhow, after I have seen him I can ask my gp for the referral to the Endo! Amazing how much better it makes you feel to have someone finally get the ball rolling! Hope you're doing well and thanks again. X 😄😄😄😄 x

[ritz]

best of luck x

once I started to put my dose of armour up the thyroid symptoms of high bp and spots started to go and the exmestane does not attack my joints as badly - but it is thinning my hair - so nothing is perfect but it is a better combination

the other thing my hospital does is acupuncture which I find helps to make me feel I have a bit more energy

I hope you find a combination that works for you