SST test for low cortisol whilst on TRANSDERMAL HRT/oestrogen gel (i.e. not oral hrt)

[InstaBeakie]

I believe that taking oral oestrogen interferes with serum cortisol levels (I think it increases it) due to increasing cortisol binding globulin. (I know that for SHBG, transdermal doesn't affect it but oral does)

I have been taking transdermal oestrogen gel - I believe that this may not have the same effect on cortisol as oral and is ok to take whilst having the SST test, but can anyone confirm?

By way of background, I have had repeated 9am cortisol tests of about 200 nmol/l and am hoping my new endo will agree to an SST test but am curious if she will make me stop hrt for 6 weeks before which I really want to avoid having to do.

[Hidden]

I'm not sure about that one - both the contraceptive pill & HRT will elevate cortisol but I don't know about transdermal oestrogen, but guess it could. You'll need to ask your Endo, you don't really want your results to be elevated because of it.

[heathermr]

I was told to stop my HRT patch for 6 weeks before a SST because it would affect the results.

Heather

[vocalEK]

This article discusses contraceptive pill but no mention of transdermal. You might be able to contact the lab and ask what medications would interfere. racgp.org.au/afp/2017/march...

[Mmrb8]

Can you please tell me what came of this? I am in similar situation. I use oestradiol gel (sandrena) and i have acutely dangerously low cortisol (less than 25 i. Almost undetectable) followi g epidural steroids so we suspect steroid induced adrenal insifficiency and i started emergency hydrocortisone 4 daya ago. I obviously need a short synacthen test soon and it will be next week but no one has mentioned coming off oestrogen and there isnt the luxury of 6 weeks to plan that anyway and i wouldnt welcome my hot flashes back anyway. I also have Hashimotos. So tje question is if i have my short synacthen test in 20 days while on sandrena will i get an accurate result. It obviously didnt raise my morning cortisol level last qeel which is almost undetectable so maybs it is irrelevant in my case. Did your doctor ask you to stop oestrrogen gel in the end?

Ps. Why are adrenal tests being discussed under Thyroid uk? Thanks