Reasons not to take medication before blood tests

[Piglet1956]

I recently went to my GP as I have severe pain in my shoulder, a bit like a mild version of frozen shoulder which I had about 5 years ago. Bloods were taken and I got a call for a GP phone appointment in 10 days time.

I got a copy of my blood results and I suspect the call is to tell me I'm overmedicated on Thyroid medication. TSH was <0.01 (0.35-5), T4 was 13.2 (9-21) and T3 7.1 (3-6).

I have Hashis and I'm currently taking 2 grains of Armour thyroid daily. I was unaware my thyroid would be tested and I took my mourning dose at my usual time between 6 and 7am and the bloods were taken at 10:30am. Could someone please remind me what to say to the GP, i.e. the reason we should take thyroid medication after having blood taken and 24 hours after the previous dose.

My GP takes nothing to do with my thyroid now as I get the medication privately. The NHS was too afraid of suppressed TSH to medicate me adequately enough to feel well. I had my private thyroid consultation and bloods done at the beginning of December 2024 and T4 and T3 levels were good. I know I am not overmedicated.

Thanks for your help as always.

[Jaydee1507 Administrator]

Having been caught out this way myself, although only on Levo, I now always dose thyroid meds accordingly prior to any blood test appointments, because its odds on that they will slip in a thyroid blood test if you have a hypo diagnosis.

There are explanations ref timings of dose prior to blood test in this pinned post: healthunlocked.com/thyroidu...

[Piglet1956 in reply to Jaydee1507]

Thank you Jaydee1507. That's really helpful information to be armed with.

[helvella Administrator]

You might something of help or interest in my blog on these issues.

helvella - Scheduling Blood Draws

Factors to consider when choosing time for blood draws. Includes links to several documents/webpages and previous HealthUnlocked posts.

Last updated 30/12/2024

Link to blog:

helvella.blogspot.com/p/hel...

[Piglet1956 in reply to helvella]

Thanks Helvella, I'll have a look.

[tattybogle]

basically , regarding the fT3 result being over range, you just need to say that when taking anything with T3 in , the fT3 level rises quickly and has reached it's peak by 3 or 4 hrs after taking last dose (which is when yours was tested) and that this peak level is relatively short lived.... by about 6 hrs from last dose the fT3 level is lower again . So , yes your peak level is slightly over range very briefly , but your average level all day is comfortably within range.

have a read down this : thyroidpatients.ca/2019/11/... free-t3-peaks-and-valleys-in-t3-and-ndt-therapy/

and look at the first graph (useful to show GP too) ...the top line of that graph shows how brief the peak fT3 level is in someone taking T4 + T3 combo therapy ( ok it possibly lasts for longer with NDT but we don't know for sure ,and GP won't understand the difference anyway, so i wouldn't worry about that )

if you want some science to baffle them with :

regarding why your TSH is so low ....see the first reply to this post : healthunlocked.com/thyroidu.... tsh-is-just-the-opinion-of-your-pituitary-about-your-dose-but-your-pituitarys-opinion-is-a-bit-warped-once-you-take-thyroid-hormone.

some other references for testing 24 hrs after last dose T4 are in the first few replies to this post : healthunlocked.com/thyroidu.... list-of-references-

[Piglet1956 in reply to tattybogle]

That's perfect tattybogle, just what I'm looking for. Thank you.

[ThyroidieGriaffe]

Hi Rose people will respond on the meds. Frozen shoulder... a good physio will always ask if you have a thyroid problem if you are female and younger than about 60.. Worth goggling, think there are threads on here too, if you want to address your GPs lack of knowledge. Alternatively try to see a physio and avoid GPs.

[Piglet1956 in reply to ThyroidieGriaffe]

Good advice. Thank you. I had a frozen shoulder around the time I was diagnosed with Hashis. Most painful thing ever and lasted ages.

[Cazlook]

ask for another blood test after a month because you feel that this is an anomaly, cx

[Piglet1956 in reply to Cazlook]

Thanks for taking the time to reply and I'll bear this in mind for the future.

[malancy]

Surely if you souce and medicate yourself your results have nothing to do with your gp. He does not treat and prescribe for you so there is nothing he can do. You feel well so carry on looking after you.

[Piglet1956 in reply to malancy]

Yes Malancy, I agree. But I suspect the GP has forgotten that and is panicked by the results which is why I need the information to educate him.