Avatar universal

Newly diagnosed (subclinical) hypothyroid

Hello, everyone. I'm curious to see if anyone has advice for me on this:

I am a university lecturer, male, 34 years old, who has had a slightly abnormal TSH levels for the past two years (at least two years, before that I was never tested). It hovers between 6.2 and 7.3. T3 and T4 are always normal, right in the middle to slightly above the middle of the range. My father is severely hypothyroid, as was my grandfather. My older brother was recently diagnosed as well, in his 40s.

This last year I began to have trouble concentrating, often having to read things two or three times to understand even the main ideas. I also became very forgetful, tired, and generally spacey. My doctor decided to put me on Synthroid (generic), 25mcg to see if it helps. I've been on it for a week, and have been having trouble sleeping. No other weird hyper symptoms.

My questions are these: Does it seem reasonable to everyone that I should start medicating for what is clearly subclinical hypothyroidism? Are there ill effects that could arise from medicating "early", meaning before I have full-blown hypothyroidism? (I figure due to my family history I will end up fully hypo at some point.) Also, could someone explain the difference between generic levo and Synthroid? I've found a lot of screeds against the generic (which is all my health plan covers), but I haven't found a good explanation as to why a rigorously manufactured generic would be less effective than the brand name.

My doctor is not an endocrinologist (specialty services are hard to get under my health plan (thank you, California state university system!), so I've been doing internet research on the topic. As I'm sure you all know, there are lots of conflicting opinions and evidence out there.

Thank you!
8 Responses
Avatar universal
An elevated TSH, along with symptoms that can be related to hypothyroidism, you certainly need further testing.  You mentioned your Free T3 and Free T4 were in the middle of the range.  When were they last tested?  Also, please post results and reference ranges shown on the lab report and we'll go from there.  
Avatar universal
Hi, thanks for the reply.

I was lasted tested a week ago. The values are:

T3 total: 109   range: 84-172 ng/dl
T3 uptake: 33.4   range: 23-36 %
T4 total: 7.4   range: 4.5-12.0 UG/DL
TSH: 7.23 mIU/L

Also negative for thyroid antibodies.
Avatar universal
Please post all your most recent blood labs you have along with the reference ranges.

I'm not a big believer in TSH but I'd say you have been hypo for a long time.  A TSH above 3.0 is considered Hypo.

The reference ranges for Free T4 and Free T3 are created FAR too wide and being in the reference range if below 50% are considered quetionable at best.

I don' t think that medicating "early" is harmful.  I personally since you are having symptoms means in fact that it is NOT "early".

Generic versus brand name has no difference as to the potency or the type of the  active T4 ingredient.  The differences come from the filler, binders and buffers that are used.  Some people will have sensitivity with or allergic reactions to some of these fillers and thus can tolerate one brand and not another.  Most peope do not have any issues with generic.

Make sure to be tested and look specifically for the FREE T4 and FREE T3 tests.  If not specifically noted to be "free" the test is for total hormone which are outdated tests of limited value.  The term "free" indicates a hormone which is unbound and thus free from being attached to a protein.  Once attached to a protein the hormone molecule is useless and inactive.  Therefore you can now see why it is so important to be tested for the active forms of the hormones which are free from the protein.

Utlimately the Free T4 is a storage  hormone that remains in your blood to be used by your body at a later date.  When the body senses the need for thyroid ho rmone, the body will convert the stored Free T4 hormone by stripping off an Iodine molecule and convert it into T3.  Some if not most of that is bound with the protein and thus useless. The remaining Free T3 hormone is the ONLY thing you body uses at the cellular level.

Therefore if there is only one thing to test for it owuld be the actual  hormone that your body's cells ACTUALLY use.  ANd that is Free T3.

Most people who find themselves symptomatic and need of thyroid medicine have reported that in order to feel well, the rule of thumb is to have BOTH of the following:

1) Free T4 (FT4) to be in the MIDDLE of the range if not slightly higher (50% of the range)

AND- that means in addition

2) Free T3 (FT3) top be in the UPPER 1/3 of the range (66.7% of range).

Notice that these are well up into the range and simply being somewhere in the range is NOT sufficient.

Everyone is different and feels well at a different level.

25 mcg of T4 is a very common starting dose, but it is only a starting dose and most people will need more.  

T4 takes up to 6 WEEKS to stabilize the level in your blood. So do not expect huge changes with such a low dose and only having just begun treatment.

I encourage everyone to keep a detailed spreadsheet of the medication, the dosage tied to the blood labs at the time along with any symptoms you have.  This way you can develop a history and can see the changes in how you feel, how that comapres to blood labs and can see medications dosage change responses in the blood labs.  This record will prove invaluable if you have to change Dr's or if you move etc.  
Avatar universal
Thank you for the reply, FlyingFool.

I posted the thyroid-related numbers from the lab report above; from what you've said it doesn't look like they've provided me with the free T3 and T4 numbers, just the totals. Does that mean I should request additional tests, or is there something you (or an endocrinologist, should I get in to see one) can glean from what I have?
Avatar universal
Well the total test is less accurate but...

The Total T4 shows that you are at 44% of the range.  And for  free T4 you want to be at 50%.  It is not a one to one comparison because you have no idea what percentags of the total are free or bound.  But ASSUMING that they are 1:1 it would seem to indicate that you may be a bit low.

The Total T3 is only at 25% of the range.  Again the rule of thumb for FREE T3 is 50% to 67% of the range.  So again if we ASSUME that they are 1:1 ratio that too would show that you are quite low.  And just common sense would seem to suggest that if you are low in total amount of the actual hormone no matter what percentage is bound, it owuld seem reasonable to expect that the amount of free and unbound T3 would be low.

Also the TSH test indicates that your pituitary gland thinks that you are low thyroid.  

So everything even with the outdated tests would indicate that you are hypo and need medication.

but you should DEMAND from this point forward to insist that you be tested for Free T4 and Free T3.
Avatar universal
Thanks again, very helpful.

Have a nice day.
1756321 tn?1547095325
If you are suffering hypothyroid symptoms it's best to start thyroid medication. Why suffer unnecessarily?  Due to your family history, it would be likely you have Hashimoto's thyroiditis. Hypothyroid symptoms may worsen to start with as natural thyroid hormone production may slow down in response to thyroxine and it takes around 4 to 6 weeks for thyroxine to build up.

This is an excerpt from The Washington Post - Drug expert explains how generics do and do not differ from brand-name drugs...

"Some people taking certain kinds of medicine say they have trouble switching to generic versions. Are they imagining it?

No. This problem involves what we call narrow therapeutic index (NTI) drugs, including anti-seizure medications, blood thinners and thyroid hormone replacements. For them to work properly, you have to maintain a specific concentration in the blood. You have to regularly check blood levels to make sure the concentration is right.

Either a brand-name or generic NTI drug can work, but once you have identified a suitable version, it may not be advisable to switch back and forth, even between two generics, because the formulation characteristics might be different and affect the blood concentration. If you want to change, you should have close blood monitoring at the beginning."
Avatar universal
Hello again,

Curious if you have some advice on this --

Per the above, I've been on 25mcg of generic levo for four weeks now, and I find myself somewhat short of breath, especially when exercising. Additionally, I've been experiencing what I think are PVCs, again usually when exercising. It's usually just one or two beats, often right upon finishing exercise and cooling down, or when hiking up a good sized hill.

Of course I'm going to mention these things to my doctor when I get my next blood test in two more weeks, but I'm curious if these symptoms are considered normal, if they are likely to go away, and if there is anything I should do immediately. Palpitations are listed in the list of possible side effects in everything I've read online, but other than saying "mention these to your doctor" they don't offer any explanation of the mechanism or advice.

Btw, I was having some PACs a few years ago and had a full cardiac workup - no problems found, great cholesterol levels, etc.
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