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Levothyroxine - What to Expect?

sazzyb

Newbie
Messages
1
Type of diabetes
Type 1
Treatment type
Pump
Hi there

Just been prescribed levothryroxine for slightly too high TSH levels following hemithyroidectomy. Starting on 50mg and see where I'm at in 6 weeks. I say slightly too high - TSH levels actually within 'normal' range but trying for a baby which apparently means best to get TSH under 2.5.

Anyhow, due to the aformentioned trying for a baby, I have pretty tight control but read that insulin levels might need adjusting on levothyroxine. Which isn't terribly helpful - does it increase insulin resistance or....? And is it for a few hours after the tablet or an all day affair? Sure I will see tomorrow when I take the first dose but with the eleventy billion things that can affect blood sugars it would be nice to know what to look out for with this new factor!

Thanks!
Sar x
 

Sazzy - I'm not T1, so won't comment on insulin sensitivity, although I didn't notice any changes to my own readings, when I started Levothyroxine. I'll tag in @LooperCat who started Levo relatively recently, and @Juicyj , whom I know are both T1 and hypothyroid.

I will say though that you are unlikely to see or feel anything immediately, on T4 therapy. Levothyroxine works on a therapeutic dose basis, meaning it needs to build up in your system for impact. That's just one of the reasons your levels will only be retested after about 6 weeks.

I'm pleased to hear your team are trying to keep your TSH quite low. For most diagnosis, nothing is done until TSH breaches 5, with symptoms or 10, if the person is symptom free.

When you have your tests, do you have TSH, FT4 and FT3 tested?

If you want to learn lots about thyroid issues, you could have a look around https://healthunlocked.com/thyroiduk They're fabulous over there, although not too many T1s that I know of.

Of course, having had your hemithyroidectomy, you may already be very familiar with the site.

Good luck with it all. Getting the thyroid balanced out isn't always a quick fix, but worth it.
 
I don’t think it’s made any difference to my insulin sensitivity, but I changed a few other things at the same time I started Levothyroxine, so it’s impossible to say for sure.
 
The only difference I noticed from starting levothyroxine many years back was a noticeable feeling of extra energy and well being. It lasted for maybe 6 months. After this I think this new found feel good factor just became the norm.
 
I started levothyroxine 25ug daily about six weeks ago. I've not noticed any changes in my insulin sensitivity. Being keto these days means I'm much more likely to spot differences like that, but, as they say... 'Your Diabetes May Vary'.
 
Colin of Kent said:
I started levothyroxine 25ug daily about six weeks ago. I've not noticed any changes in my insulin sensitivity. Being keto these days means I'm much more likely to spot differences like that, but, as they say... 'Your Diabetes May Vary'.
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That's an incredibly low dose, Colin, although they medics do sometimes start very slowly. I was started on 25mcgr, but that was because my GP was being ultra cautious.

Are you scheduled to have checks to see where your levels are heading, and monitor any siymptoms you may have had before?
 
I was regularly tested for thyroid issues for as long as I can remember (certainly for at least 40 years before being finally diagnosed). I didn't notice any difference at all once I started on the Levo, in fact I hadn't noticed any symptoms anyway. It was something about my face that prompted every new GP to test me - no idea what though. I did wonder if the T2 (when I was finally diagnosed with it) was causing or masking the symptoms because I've had T2 symptoms and PCOS back in to my early 20s (mid 60s now) - I just didn't know they were symptoms of T2 at the time.
 
The levels of Thyroxine are always started low - too high and you can get palpitations and other unpleasant side effects - I was eventually on 200 micrograms, but started at 50 - my TSH was several thousand times higher than the top end of the normal range when I was finally diagnosed. I can still remember the sensation of my hands and feet being in warm water which came over me on the third day after starting replacement therapy.
 
I don't have any tests booked yet, but will do so soon, as I've now been on it six weeks. I've not noticed any changes yet in my symptoms.

I'm seeing my endocrinologist this Friday, so it will be interesting to hear his views. I did suggest to him before that my thyroid may be off keel, but he didn't seem to think it was then.
 

Many, many, many people have symptoms before their blood tests reach the diagnostic thresholds we work to in UK.

In UK, treatment is considered, once a person's TSH goes over 5.0. If they are symptomless, its 10. In the US, the diagnostic threshold is 3.0.

The challenge with thyroid issues is the symptoms are also symptoms for a whole slew of other conditions too. And don't even start me on the uselessness of using TSH as a metric. It's a signalling hormone, it doesn't actually give any info on how the thyroid is actually performing, only how hard it's working to try to get the thyroid into action.

When you have your tests, it is thought to be advantageous to be tested as early a study possible, and 24 hours after any Levothyroxine.

Good luck with it all, but don't be alarmed if you're titrated up a bit. The average therapeutic dose of levothyroxine in 100-200mcgr. Often 0.6mcgr per kilo body weight is used as a very rough rule of thumb, but that's all it is.
 
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I was on Levothroxine before being diagnosed T1. It has made no difference to me and I take 125mg daily. My TSH levels have remained quire consistent.
 
Levothyroxine often makes it a little easy for people to lose waight if they have gained waight due to an underactive thyroid. Lose of body fat often decrease inslin resistance.

I expect you are allready controlling your inslin based on BG tightly enough that any effect the Levothyroxine has will be corrected for without needing addational action.
 
@ringi - Reading thyroid fora, as I have done on my journey, I'd be a bit wary of using easy and weight loss together for those with hypothyroidism, however I think I understand your sentiment.
 
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