Aa
OK to take synthroid at night?
I know from reading the forums that synthroid is to be taken in the morning at least an hour before eating. This is difficult for me to do as I need to eat after I wake up, otherwise my blood sugar drops and I get very shaky. Would it be fine to take my synthroid before I go to bed after all my eating is done for the day as long as I do it consistently?
Also, T-4 takes 7 hours before starting absorptions, last 6 days in our system and is accumative. What you take today/night will be tomorrows effects.
TSH has a pulsate action, being lower in the early AM and highest in the PM. That is probably why for 6 years I woke up 2 hours or so after going to sleep and staying awake. Also the reason it is suggested that Hypers get their test done early in the AM as possible and hypos in the PM as late as possible, some doctors claim that it doesn't make a difference (?).
GL
Please don't shoot the messenger!
TSH has a pulsate action, being lower in the early AM and highest in the PM. That is probably why for 6 years I woke up 2 hours or so after going to sleep and staying awake. Also the reason it is suggested that Hypers get their test done early in the AM as possible and hypos in the PM as late as possible, some doctors claim that it doesn't make a difference (?).
GL
Please don't shoot the messenger!
Thanks for all the feedback. I will definitely discuss this with my endo and the pharmacist.
When GravesLady says that T-4 takes 7 hours before starting absorption, I am wondering if this is related to the body's conversion of T-4 into T-3? My grasp of physiology in this area is not strong, but I learned from what seemed to be a reputable source that after taking a dose of levothyroxine, the drug reaches its peak in the bloodstream about two hours later (with the usual individual differences that cause the time to vary from person to person).
What seems odd, if you back off and think about it, is that synthetic levothyroxine affects sleep in any way, for any of us. As an endocrinologist commented, the slowness with which our bodies excrete levothyroxine means that each day's dose is not adding dramatically to the level of the drug that already is there. If you stopped taking levothyroxine tomorrow, you would have 50% of the current level in your bloodstream a week from now. The endocrinologist I am quoting said that given the slow-excretion situation, the post-dosage "peak" is really a mini-peak.
The mini-peak must matter, because as we all know, the standard advice about levothyroxine is "take it in the morning." I do not know how many people are kept awake at night if they take levothyroxine any later than in the morning, but it must be many people...possibly most, since the "take it in the morning" advice is indeed the standard? All the same, not everyone turns into an insomniac by taking levothroid in the afternoon, or at least that is what I was told before I began experimenting with dosing myself late in the day.
I want to say to Lake Lover that I never connected my struggles with sleep and hypothyroidism, either, especially because for many years, the same kinds of sleep struggles were a pre-menopausal and post-menopausal symptom of a low level of estrogen. Most descriptions of thyroid disorders make a person think that the LAST thing in the world she wants to do if she has trouble sleeping is take levothyroxine. I wonder how unusual I am, which is an unanswerable question, of course, but you can't blame me for wondering!
What seems odd, if you back off and think about it, is that synthetic levothyroxine affects sleep in any way, for any of us. As an endocrinologist commented, the slowness with which our bodies excrete levothyroxine means that each day's dose is not adding dramatically to the level of the drug that already is there. If you stopped taking levothyroxine tomorrow, you would have 50% of the current level in your bloodstream a week from now. The endocrinologist I am quoting said that given the slow-excretion situation, the post-dosage "peak" is really a mini-peak.
The mini-peak must matter, because as we all know, the standard advice about levothyroxine is "take it in the morning." I do not know how many people are kept awake at night if they take levothyroxine any later than in the morning, but it must be many people...possibly most, since the "take it in the morning" advice is indeed the standard? All the same, not everyone turns into an insomniac by taking levothroid in the afternoon, or at least that is what I was told before I began experimenting with dosing myself late in the day.
I want to say to Lake Lover that I never connected my struggles with sleep and hypothyroidism, either, especially because for many years, the same kinds of sleep struggles were a pre-menopausal and post-menopausal symptom of a low level of estrogen. Most descriptions of thyroid disorders make a person think that the LAST thing in the world she wants to do if she has trouble sleeping is take levothyroxine. I wonder how unusual I am, which is an unanswerable question, of course, but you can't blame me for wondering!
Pharmacokinetics: Levothyroxine (T-4) Synthroid, Lexovyl, etc.
Half-life is 6 to 7 days in the euthyroid subject.
Half-life is shortened in hyperthyroidism 3-4 days
Half life is prolonged in hypothyroidism and in pregnancy
9-10 days
Absorption amounts up to 80%, rest is eliminated through the urine.
Max absorption time is approximately 5 to 6 hours. (OK so I was a little off)
Half-life is 6 to 7 days in the euthyroid subject.
Half-life is shortened in hyperthyroidism 3-4 days
Half life is prolonged in hypothyroidism and in pregnancy
9-10 days
Absorption amounts up to 80%, rest is eliminated through the urine.
Max absorption time is approximately 5 to 6 hours. (OK so I was a little off)
So you were a little off...it was only a little, and you provided an excellent overview. Thank you! You filled in some knowledge gaps for me.
Just discovered this board. Interesting reading your long and informative posts, Jenny. Something with one little piece related to the symptom of insomnia, which I also had...
I went two years without a diagnosis of hypothyroidism. During that time, I got progressively worse. Exhausted, detached feeling, dizzy, slow pounding heart beat at night, numbness and other neurological problems, and reactive hypoglycemia. My whole body was going wacky and I felt like a wreck. The hypoglycemic attacks -- I could get from drinking a glass of juice -- and during one I fainted and smashed my head. I've never fainted in my whole life. On a daily basis almost, for about six months, I felt I was going to faint at some point. I learned to control my diet. (After I got on medication, that and all my other symptoms disappeared.)
In the beginning of the two years, my symptoms were mild and I was oversleeping by about an hour compared to my usual eight hours, which is classic. However, it turned to the opposite, and for over a year, I had insomnia and would fall asleep only to awaken after four or five hours at most, unable to fall back asleep. I would awaken at night feeling dead, a few times during the night. My limbs would be asleep, my heart pounding out of my chest practically, and very slowly. For a minute after I awoke at night, I would feel really dead, and then I would revive a bit.
Through this period, I kept running -- I run every day and am a former professional athlete -- because I found that if I didn't run or bike or do something, even though I felt like a zombie, I would feel so horrible I couldn't stand it. Later I would find out from an endo, that physical activity stimulates the thyroid to produce hormone.
I belonged to a medical plan, and saw my doctor frequently. At first, he said I may have a virus, and adopted a "wait and see" posture. Twice I went to an ER, following hypoglycemic attacks, and had a regular blood workup (not including TSH) and a brain scan for tumor. No tumor. After many visits, every one where I prepared a list and narrative of my symptoms and experience, my doctor would do nothing. Finally, on one visit, I saw him through a crack in the door, talking to a nurse right after both had been in the office with me, and he made a drinking motion with his hand, and they laughed. I realized, he thought I was an alcoholic, and for over a year, had just been dismissing my symptoms as connected to those of a drinker! After all, he gave me finger stick tests to proove my blood sugar was not low. (Of course it was normal, because I couldn't drink a few glasses of juice and drive to the doctor and pass out on the way.) Oddly, I do not drink, at all. I'm a health fanatic and even a glass of wine makes me feel bad the next day. I discovered that when I was 20.
My doctor had a clinical basis for suspecting I drank though, aside from my behavior. In the blood test I got at an ER, all it showed was that my potassium was low. I would later read that low potassium is a problem found in alcoholics. Alcohol leaches the body of potassium, or something.
I got so discouraged, I quit my job and moved to a remote place so I could die or just start getting well. I controlled my diet strictly to avoid hypoglycemic attacks.
But, I ended up going to another doctor, because my heart started doing even weirder things, like fluttering. He gave me a TSH on the first visit. TSH was 11 and he started me on levothyroxine and in two weeks I popped back into reality. I was born again. Cured. I could sleep again. Took me almost an entire year to recover my health fully though.
Anyway, the thing about insomnia vs. oversleeping is what prevented me from diagnosing myself, via the extant information available on the web at the time, including Thyroid Mary's "comprehensive" site. That, and the red herring symptom I had of hypoglycemic attacks. At the time, 1997, there were very few medical sites on the web, and it just so happend that none of them listed the extended symptom set of hypothyroism, which would include insomnia, and reactive hypoglycemia. (The latter found in maybe 5% of hypothyroid patients.)
Back to dosing. The cummulative effect is real, so I agree with what some of the other posters wrote about that. You get a small bump from what you take that morning, but it is the cummulative amount for 6 days or so. You could overdose by 50% one one day, and may not even feel it, but if you continue to overdose, even by 10% for several days in a row, you are in for a feeling of hyperthyroidism after three days, as it builds.
I went to an endo once, about 6 months after my diagnosis, because I had so many questions that my GP couldn't answer. (Some GPs know very little about thyroid, including a close friend of mine.) I wanted to know things like, how damaging was it for me to be so ill for two years with this condition untreated. Most of the questions I had, the endo said she didn't have an answer.
She said the thyroid requirement could fluctuate in some people, and that I shouldn't be afriad to take a bit more, on a day I feel hypo, or reduce it on a hyper day, but always by small amounts.
A lot of exercise can stimulate the thyroid, so if I worked out for two or three hours, I could take that into consideration.
The first year, I was confused about dosing and symptoms or being hypo or hyper. Doctor said I was fine with a TSH of 1.5, but I discovered for me, that was WAY to low, and I'm more comfortable with a TSH of over 5 but under 6. You have to find YOUR best level. Not what the doctor thinks is fine from a number within that huge range.
When I am too hyper (for me below TSH=4.5) I feel tight, can't sleep well, and may get ringing in the ears, and a faster pulse rate, up in the 80's.
When I am hypo, I feel slightly tired, a little bit foggy, and my pulse rate may drop to below my regular resting pulse of 62. I'm very sensitive to it and better than any TSH test at regulating my dose.
Anyway, back to the original topic. Because of the great explanation Jenny gave, how the thyroid may secrete less hormone at night, I believe that to be true, since its main function is controlling metabolism. Naturally, at night, you aren't eating or digesting as much food in the middle of the night as we are in the middle of the day. I don't eat at least 2 hours before I go to bed anyway.
I've experiment with night time dose, and split dose, but morning dose works best for me, and now, I actually prefer waiting one hour before I wake up, before I eat anything. But, although you should probably ask your doctor, I doubt that having a glass of juice would interfere with the dose of hormone, if you wanted to eat or drink something first thing in the morning.
The worst foods for blocking absorption are calcium and soy I think, or anything containing cations.
If you want to eat a full breakfast in the morning, you can also ask for a bigger dose, by 8% I think it is. But then you kind of have to wonder, what foods you eat may be blocking the absorption more than others. So, empty stomach is most reliable.
Sorry for writing so much. Didn't want to blind anyone!
I went two years without a diagnosis of hypothyroidism. During that time, I got progressively worse. Exhausted, detached feeling, dizzy, slow pounding heart beat at night, numbness and other neurological problems, and reactive hypoglycemia. My whole body was going wacky and I felt like a wreck. The hypoglycemic attacks -- I could get from drinking a glass of juice -- and during one I fainted and smashed my head. I've never fainted in my whole life. On a daily basis almost, for about six months, I felt I was going to faint at some point. I learned to control my diet. (After I got on medication, that and all my other symptoms disappeared.)
In the beginning of the two years, my symptoms were mild and I was oversleeping by about an hour compared to my usual eight hours, which is classic. However, it turned to the opposite, and for over a year, I had insomnia and would fall asleep only to awaken after four or five hours at most, unable to fall back asleep. I would awaken at night feeling dead, a few times during the night. My limbs would be asleep, my heart pounding out of my chest practically, and very slowly. For a minute after I awoke at night, I would feel really dead, and then I would revive a bit.
Through this period, I kept running -- I run every day and am a former professional athlete -- because I found that if I didn't run or bike or do something, even though I felt like a zombie, I would feel so horrible I couldn't stand it. Later I would find out from an endo, that physical activity stimulates the thyroid to produce hormone.
I belonged to a medical plan, and saw my doctor frequently. At first, he said I may have a virus, and adopted a "wait and see" posture. Twice I went to an ER, following hypoglycemic attacks, and had a regular blood workup (not including TSH) and a brain scan for tumor. No tumor. After many visits, every one where I prepared a list and narrative of my symptoms and experience, my doctor would do nothing. Finally, on one visit, I saw him through a crack in the door, talking to a nurse right after both had been in the office with me, and he made a drinking motion with his hand, and they laughed. I realized, he thought I was an alcoholic, and for over a year, had just been dismissing my symptoms as connected to those of a drinker! After all, he gave me finger stick tests to proove my blood sugar was not low. (Of course it was normal, because I couldn't drink a few glasses of juice and drive to the doctor and pass out on the way.) Oddly, I do not drink, at all. I'm a health fanatic and even a glass of wine makes me feel bad the next day. I discovered that when I was 20.
My doctor had a clinical basis for suspecting I drank though, aside from my behavior. In the blood test I got at an ER, all it showed was that my potassium was low. I would later read that low potassium is a problem found in alcoholics. Alcohol leaches the body of potassium, or something.
I got so discouraged, I quit my job and moved to a remote place so I could die or just start getting well. I controlled my diet strictly to avoid hypoglycemic attacks.
But, I ended up going to another doctor, because my heart started doing even weirder things, like fluttering. He gave me a TSH on the first visit. TSH was 11 and he started me on levothyroxine and in two weeks I popped back into reality. I was born again. Cured. I could sleep again. Took me almost an entire year to recover my health fully though.
Anyway, the thing about insomnia vs. oversleeping is what prevented me from diagnosing myself, via the extant information available on the web at the time, including Thyroid Mary's "comprehensive" site. That, and the red herring symptom I had of hypoglycemic attacks. At the time, 1997, there were very few medical sites on the web, and it just so happend that none of them listed the extended symptom set of hypothyroism, which would include insomnia, and reactive hypoglycemia. (The latter found in maybe 5% of hypothyroid patients.)
Back to dosing. The cummulative effect is real, so I agree with what some of the other posters wrote about that. You get a small bump from what you take that morning, but it is the cummulative amount for 6 days or so. You could overdose by 50% one one day, and may not even feel it, but if you continue to overdose, even by 10% for several days in a row, you are in for a feeling of hyperthyroidism after three days, as it builds.
I went to an endo once, about 6 months after my diagnosis, because I had so many questions that my GP couldn't answer. (Some GPs know very little about thyroid, including a close friend of mine.) I wanted to know things like, how damaging was it for me to be so ill for two years with this condition untreated. Most of the questions I had, the endo said she didn't have an answer.
She said the thyroid requirement could fluctuate in some people, and that I shouldn't be afriad to take a bit more, on a day I feel hypo, or reduce it on a hyper day, but always by small amounts.
A lot of exercise can stimulate the thyroid, so if I worked out for two or three hours, I could take that into consideration.
The first year, I was confused about dosing and symptoms or being hypo or hyper. Doctor said I was fine with a TSH of 1.5, but I discovered for me, that was WAY to low, and I'm more comfortable with a TSH of over 5 but under 6. You have to find YOUR best level. Not what the doctor thinks is fine from a number within that huge range.
When I am too hyper (for me below TSH=4.5) I feel tight, can't sleep well, and may get ringing in the ears, and a faster pulse rate, up in the 80's.
When I am hypo, I feel slightly tired, a little bit foggy, and my pulse rate may drop to below my regular resting pulse of 62. I'm very sensitive to it and better than any TSH test at regulating my dose.
Anyway, back to the original topic. Because of the great explanation Jenny gave, how the thyroid may secrete less hormone at night, I believe that to be true, since its main function is controlling metabolism. Naturally, at night, you aren't eating or digesting as much food in the middle of the night as we are in the middle of the day. I don't eat at least 2 hours before I go to bed anyway.
I've experiment with night time dose, and split dose, but morning dose works best for me, and now, I actually prefer waiting one hour before I wake up, before I eat anything. But, although you should probably ask your doctor, I doubt that having a glass of juice would interfere with the dose of hormone, if you wanted to eat or drink something first thing in the morning.
The worst foods for blocking absorption are calcium and soy I think, or anything containing cations.
If you want to eat a full breakfast in the morning, you can also ask for a bigger dose, by 8% I think it is. But then you kind of have to wonder, what foods you eat may be blocking the absorption more than others. So, empty stomach is most reliable.
Sorry for writing so much. Didn't want to blind anyone!
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