I was taking Levothyroxine 50mcg and my doctor needed to increase it due to my numbers being slightly Hypo, (5.75. Normal range ends at 5.00) The increase was 50mcg more just on Sundays. However, 3 and a half weeks into this new dose, I changed pharmacies and they gave me a different Levothyroxine (different manufacturer) While waiting for it to be filled, I missed about 3 days of my doses. When I began taking the new one, after 2 days I started feeling VERY hot and sweating a lot. So I stopped taking it for the past two days. I happened to have an appointment with a GYN today and asked him to check my thyroid. Results were just posted, 7.14 (Normal range is 5.7) So, knowing the half life, I'm concerned that if the initial 3 missed doses last week and 2 missed this week affected the result or not? The GYN had said it would show my levels for the past 2 weeks. I don't feel hypo, quite the opposite. So I'm assuming switching the Levoth did not agree with me. The pharmacy is unsure they can get the one I was taking but if they do, it will be a week before it comes in.
I won't be talking to my regular doctor until Thursday. But I'm nervous that she will want to increase my dose based on the numbers. It doesn't make any sense that my starting number was 5.75 and after the increase and 5 misses doses it would go to 7.14 .... ?
Any thoughts on this mess I've made would be appreciated.
missing a few doses will not have a huge effect on your levels - this is becuase the T4 med has a long half life (days).
However, the change in meds may be disagreeing with you. Once you find a med that works you should stick with it. I would be trying to get back to the original med. The dose of thyroid med is brand dependent.
Also optimal TSH is not just inside the range, but actually likely in the range of 1 - 3, with most people feeling best between 1 - 2. 5.0 is still too high.
You should also ask your doctor to test for FT3 and FT4. these are the actual thyroid hormones (not an indicator as TSH is). Ft3 and FT4 should be at least middle of the reference range.
Your dose may need to increase over time, depending on the cause of the hypothyroid. In many cases it is progressive.
I would try to go back to your original med and take it consistently for 4 weeks, then test again and readjust appropriately.
Yes, the missed doses would have affected your levels.
Your doctor should be testing FREE T3 (FT3) and FREE T4 (FT4) along with TSH every time blood is drawn. TSH is a pituitary hormone and influenced by any number of factors besides thyroid hormone levels. If you feel hyper even though your TSH is high, it might be because TSH is not reliable in your case.
Be sure your regular doctor knows about the skipped doses. That should make her less likely to want to increase your dose.
"It doesn't make any sense that my starting number was 5.75 and after the increase and 5 misses doses it would go to 7.14 .... ?" Actually, it makes perfect sense. Just take a look at the past week. You missed 5 doses (5 X 50 = 250), and you only added in 50. So, you're down 200 mcg from the previous week. Since you are only taking 400 mcg per week, that's half what you should be taking. Your TSH is indicating that you are more hypo than you were last week.
Do you understanf FT3 and FT4? I'll be happy to explain, but don't want to tell you what you already know.
Yes, I discussed with her testing the FT3 and 4. Both my doctor and my GYN said it would not change the way they treated the hypothyroidism. They said those levels would be low also so they test standard TSH. For now, I am just accepting it. If I am going to have a progressive problem, I am going to ask to be seen by a specialist.
Now that you explained it, the missed doses do make sense now. If I have to wait a week to get the correct Levothyroxine, is that too long to go untreated? This shouldn't be so complicated ... I am definitely frustrated. :(
Just don't hesitate to ask for a referral if you don't feel better. Treating by TSH alone seldom works, but you may be one of the lucky ones.
A week isn't too long to go untreated in the sense that it's not going to kill you or anything. However, combined with the past week of less than half dose, you could be starting to see your hypo symptoms come back of worsen.
Levo builds in your blood over 4-6 weeks. How you feel today depends on the meds you've taken over the past 4-6 weeks. So, you can't just not take it for a week, start taking it again and be all better. Until that missed couple of weeks is 4-6 weeks behind you, you're going to be feeling the effects of it(progressively less as it moves further behind you).
Are you going to ask your doctor for a script for a name brand? That's the best way to insure that it comes from the same manufacturer every time. The added bonus is that you won't have to go without your meds for so long because it will be immediately available at your pharmacy.
Consistency is the key to managing hypo. A missed dose here or there isn't going to hurt anything, but when they start building up, they throw everything off including both your symptoms and your lab reliability.
Different manufacturers use different fillers, buffers and dyes in the pill. Often times people will have a reaction to some of these buffers that for whatever reason isn't tolerated. Add in that because of the different fillers etc, the absorption may be different. So one pill you may get little T4 absorbed and another you may get much more.
That is why the posters above stated that manufacturer of the T4 med is important.
Speaking of absorption. Have you changed your routine of taking the meds? They should be separated by food by at least 1/2 hour and by supplements like vitamins by like 4 hours. Calcium in particular is known to have a detrimental effect on absorption of thyroid meds.
So ideally thyroid meds should be taken on an empty stomach with only water.
Adjusting thyroid meds accurately using only TSH is almost impossible.
Okay I had written down the missed doses. My last full weekly dose ended on March 6th. I then missed a dose on the 7th and 8th. The blood work was done yesterday, the 13th. (The 3rd + missed dose was the 12th & 13th) So, wouldn't the TSH show what was in my blood prior to the 6th? I'm still confused that the level was 7.14 since I'd been taking it regularly and had the slight increase in Levo. If the half life is 7 days, I should have had a lower TSH?
I had my Levo transfered back to my old pharmacy and will be back on track tomorrow. Hopefully, I will speak to my doctor and g over all of this with her. I'm assuming she's going to want me to take it another 4-6 weeks before we re-check the level. If by then there is still a problem, I will ask for a referral and see an Endo.
I do take the Levo on an empty stomach in the morning and wait 1/2 hour before eating. I have never mixed supplements with it, etc. I'm very religious about taking it. This wouldn't have happened had the pharmacy had the brand I take. But what they did give me was awful. Not just the hot flushes and sweating, I had a face rash and swelling too. So yes, I'm going to make sure this switch doesn't happen again.
First off, TSH is counterintuitive. The higher the TSH, the more hypo you are, the lower the more hyper.
Your blood was drawn on the 13th, so your TSH on the 13th was 7.14. Noo, it would not have shown what was in your blood prior to the 6th, it shows what's in your blood when it's drawn. Half life only refers to how long the meds stay in your system. Since you missed your meds on the 7th, 8th, 12th and 13th, you had missed 4 doses in the week just prior to having your blood drawn. That would be reflected in the TSH of the 13th and would tend to make you more hypo and raise your TSH. Your TSH only changed from 5.75 to 7.14, which is really not a significant change. That difference could easily be explained by circadian TSH variations.
Half life is a bit of a difficult concept to explain, so I hope I've made it clearer. If not, let me know, and I'll try again.
Yes, now that you've missed several doses in a week, I would expect your doctor to want you to wait until you've been on a steady dose for 4-6 weeks before retesting.
It sounds like you might have had an allergic reaction to one of the fillers in the new meds. There's no reason you shouldn't go back to your old generic, except that this might happen again since even the same pharmacy often changes manufactureres of generics. Just refill your scripts as early as you can so you have time to regroup if they switch things on you.
I think your GYN is trying to oversimplify this and therefore making it even more confusing.
First of all, levo stays in your system for 4-6 weeks altogether. So, if you stop taking it today, its effect will gradually go out of your blood for 4-6 weeks until it is gone.
So, your TSH level today reflects everything you've take for the past 4-6 weeks, with what you took today having the biggest effect and what you took 4-6 weeks ago having the smallest effect.
The half life of T4 is about a week. That means that if you take 50 mcg today, a week from now 25 mcg will still be in your blood. Of course, it gradually goes out of your body over that week.
Let’s take a week as an example and see how it goes (T=today, T-1=yesterday, etc.). You take 50 mcg every day. Here’s what’s left of everything you took for the past week:
T 50 mcg
T-1 46.5 mcg
T-2 43 mcg
T-4 39.5 mcg
T-5 36 mcg
T-6 32.5 mcg
T-7 29 mcg
T-8 25.5 mcg
So, today, all that is still in your blood. Add it up, and it’s a total of 302 mcg. Now, remember that this is a continuous process, so in a week you ALWAYS have 302 mcg left of your past weekly intake (if you take 50 mcg every day).
Now, let’s look at the week you missed several doses (from the 13th back a week):
T 0 mcg
T-1 0 mcg
T-2 43 mcg
T-4 39.5 mcg
T-5 0 mcg
T-6 0 mcg
T-7 58 mcg (assuming this was the Sunday you took 100 instead of 50)
T-8 25.5 mcg
That’s 166 mcg, when you should have had 302.
So, you can see that everything you’ve taken (or not) in the past week is still affecting your levels. Rather than a week, the whole process goes on for 4-6 weeks with the effects diminishing the further back you go.
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