Best time for blood tests?

[Lambchop35]

Last time i had my bloods tested for a possible thyroid issue, it was triggered by sudden weight gain of a stone, fatigue, mental fog, headaches, anxiety, dermatitis, apathy. I had mid range antibodies, slightly below range ft3, just in range ft4, normal range tsh and borderline low ferritin.

TPO antibodies <33 (0.00-59.00)

Free T3 = 3.7 (3.90-6.80)

Free T4 = 11.5 (11.00 - 23.00)

TSH = 1.13 (0.35 - 5.00)

Ferretin = 17 (12.00 - 300.00)

When i finally spike with my gp, she was quite abrupt with me and said there was nothing really the matter. It was a phone appointment and i had it after not being able to sleep, due to nerves about her opinion, after a night shift. I was 'tired and emotional', so i didn't challenge her on it, feeling silly and lacking in confidence.

I have since after a good sleep and looking into this in more detail feel angry and failed by her. I have arranged for some blood tests with medicheck, the pack came through on thursday.

I last had my blood tests done immediately after finishing a night shift (working 10pm -8am) at approx 9.30 in the morning. During the night I eat and drink at my desk, including caffeinated drinks and ready meals. Is it possible this may have impacted my test results in any way? Is there an optimal time of day to have bloods taken, when trying to work out what is wrong with my thyroid? I'm not currently on shift, so was hoping to get them taken at about 9am, at the local private hospital for medichecks.

Thanks

[SeasideSusie Remembering]

Always advised here is the earliest possible time for blood draw (no later than 9am), fast overnight although you can drink water. This gives the highest possible TSH - TSH is highest early morning and lowers throughout the day, TSH also lowers after eating - and a high TSH is needed for diagnosis.

Post your new results when you have them and members will interpret them and make suggestions.

[Lambchop35 in reply to SeasideSusie]

Another poster looked at my original results, and said they thought it could indicate secondary hypothyroidism. My GP shut me down so quickly about the whole thing, i hadn't dare ask for any other tests. I'm getting my ft3, ft4 and tsh done again. Along with b12, iron, ferritin, Vit D and female hormones including prolactin. It's very reassuring to have a group like this to discuss things with. Thanks for such quick responses. I'll post my new results when i get them, i assume by next weekend.

[Mamapea1 in reply to Lambchop35]

Good luck with getting to the bottom of it Clarice83 ~ I am also a refugee from the despicable treatment and bad attitude of my GP ~ one wonders what they're being paid for when it comes to thyroid problems! I know how you feel, I've been 'tired and emotional' for 25 years and GP has been completely indifferent about my pain and inability to function.😕. Even written derogatory remarks in my medical notes about me, whilst pretending to 'help'😨

When you try to get listened to, they are arrogant and rude ~ there's so many members on this forum ~ we can't all be moaners and malingerers! Why should we all be made to feel anxious about trying to obtain adequate diagnosis and treatment?? Sorry for rant, but your post is so typical of how they make patients feel, and it really annoys me.

Try not to feel nervous about standing your ground and don't be talked down to. Good job you found this forum, lots of help and good advice here ~ from knowledgeable members 👍. Awful we have to pay for our own tests and meds due to their incompetence. At least you're in the right place now. Take care and don't worry ✨🍀✨ x

[Lambchop35 in reply to Mamapea1]

Thank you for your reply. It sounds like you've been on the wrong end of a GP far longer than I have. I am sorry things have been so difficult for you. It seems to be a common complaint with thyroid issues as you say. I have my fingers crossed, that my full battery of private tests will bolster my argument, however after ordering and receiving my bloods pack, I've read in other posts that they aren't always even looked at by doctors.

I hope you aren't too disillusioned. I'm angry on your behalf, that they were so disrespectful in your notes... that could prejudice future doctors and hinder treatment.

[jimh111]

Certainly mild central hypothyroidism, both fT3and fT4 are low. If you have the blood taken early morning when TSH is a little higher you will be shooting yourself in the foot. A higher TSH will work against a central hypothyroidism diagnosis and may push fT3 and fT4 up a little. In any event it is always better to have the blood taken later in the day when hormone levels are more stable.

You will need to be firm with your GP and polite if possible.

[AnnaSo in reply to jimh111]

Hi Jim! I hope you don’t mind me asking, I am due for a thyroid panel test tomorrow, inclusive of vitamins, minerals as well. This is to establish whether my switch to T3/T4 combo (previously T4 only), supplementing and Iron injections are working. To be honest I am not feeling much of a difference but been only two months. At what time would you say I should go? Also do I take my meds as usual beforehand? There are so many options on this but I know you’re very knowledgeable and would appreciate your take on this. Thanks!

[jimh111 in reply to AnnaSo]

Anna, I don't want to drift off Clarice's post (I have a habit of drifting off) so I will give a general answer. TSH goes though a daily cycle with the highest values around 2 am. TSH levels fall during the morning and level out during the afternoon befoe rising in the evening. Many patients have difficulty getting a diagnosis of hypothyroidism (based on an elevated TSH) so they have the blood taken early morning, to get a slightly higher TSH and more chance of being diagnosed. They also fast since it was thought this would elevate the TSH also, this is not the case, the early research measured TSH before and after breakfast, the drop in TSH was due to the later blood draw. I don't like trying to elevate the TSH to get a diagnosis, it puts the attention on TSH rather than signs and sympotoms.

My view is that you should not have the blood taken early morning. It will give a slightly higher TSH value but at this time of day TSH is changing rapidly and you will find it more difficult to compare with previous results. I take the view that you want the most accurate result in the long run. Other patients definitely disagree on this. In your case and in Clarice's case your TSH is rather low for the hormone levels you have, so trying to get your TSH higher will make it more difficult to get your doctor to appreciate it is your low TSH that is causing low hormone levels.

As regarding thyroid medication there is general agreement that you should not have the blood taken just after taking thyroid hormone. I would tend to leave at least three hours although with levothyroxine it doesn't matter much, the long half life of levothyroxine means that each daily dose has a small effect. In order to get the most accurate result with T3 medication I would have the blood taken about half way between two doses. This will give an approximately average level.

[AnnaSo in reply to jimh111]

Thank you so much! I am really curious what the results will show now that I’m on T3/T4 combo (this is a first for me, been on Levo only for 12 years).