Triton

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Levothyroxine is usually taken as a single daily dose, usually but have some patients taking it twice, even three times a day. Can't figure out the benefit of such taking. Or maybe I split hairs.
 

BMBiology

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Levothyroxine has a 7 day half life. What's the point of taking it twice or three times a day?
 
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Triton

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I don't think I've ever seen levothryoxine dosed bid or tid. Where did you see this?
In the UK :)

not often, rarely in fact, but still...
yesterday i was so curious why three times a day, that i asked the customer to the consultation room for a quick chat...and he had no idea why (i will call the doctor anyway to sort it out). It is quite possible that some patients taking two tablets e.g. 100mcg and 25mcg just don't realize that the tablets should be taken at a time.
or maybe there's some other logical explanation, and i have missed something.
 

MountainPharmD

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Levothyroxine is usually taken as a single daily dose, usually but have some patients taking it twice, even three times a day. Can't figure out the benefit of such taking. Or maybe I split hairs.
An endocrinologist in Colorado was prescribing Armour Thyroid QID. He said he believed there was a diurnal variation in thyroid hormone levels. He felt taking lower doses several times a day was a closer approximation of the bodies own release of thyroid hormones. Obviously he is in the minority.
 

SpirivaSunrise

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An endocrinologist in Colorado was prescribing Armour Thyroid QID. He said he believed there was a diurnal variation in thyroid hormone levels. He felt taking lower doses several times a day was a closer approximation of the bodies own release of thyroid hormones. Obviously he is in the minority.
I've seen similar dosing too; sometimes with a little Cytomel T3 thrown in for good measure!


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Triton

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American Thyroid Association advices to take once daily…
 
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Triton

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have you ever seen levothyroxine 600mcg in tabs a day?! maybe more?
 
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RxWildcat

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An endocrinologist in Colorado was prescribing Armour Thyroid QID. He said he believed there was a diurnal variation in thyroid hormone levels. He felt taking lower doses several times a day was a closer approximation of the bodies own release of thyroid hormones. Obviously he is in the minority.

I bet that dosing schedule worked out real well with patient compliance...can you imagine taking that stinking stuff all throughout the day?
 
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WVUPharm2007

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Ibemoe

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what are your thoughts on t3 takin with clenbuterol for weightloss. i have seen this by many guys at my local gym and it seems to work wonders. i understand its a form of steriod, but what are the sideeffects with taking the t3
 

npage148

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what are your thoughts on t3 takin with clenbuterol for weightloss. i have seen this by many guys at my local gym and it seems to work wonders. i understand its a form of steriod, but what are the sideeffects with taking the t3
It's all fine and dandy until you end up with CHF at 35
 
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Vitamin K

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what are your thoughts on t3 takin with clenbuterol for weightloss. i have seen this by many guys at my local gym and it seems to work wonders. i understand its a form of steriod, but what are the sideeffects with taking the t3
Its done by a lot of bodybuilders, but extra stupid if you ask me. Not only are you risking your natural thyroid function by pumping your body full of t3 that you dont need, but there have been a few studies with clenbuterol that showed that it actually caused heart cell death in rats. Theres a reason that its only intended for animals. Stupid.
 

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linksys

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This is probably a dumb question, but shouldn't there be some kind of differentiating factor regulating the PROPER usage of thyroxine? For example, having unique uses for EACH brand name? Some discretion between Tirosint, Novothyrox, Levoxyl, Synthroid, Unithroid, Levothroid, and Levothyroxine would be nice...

Whenever I do a search regarding this issue, it always comes up with the same three disorders that t4 treats: hypothyroidism, hashimoto's, and goiter. What about broadening the treatment horizons for the utilization of each unique T4 medication?

Or is it all just a farcical hoax?
 

npage148

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The are all T4 and there is nothing unique about them regardless of what tarted up reps will tell you. PROPER dosing is the same for each one. If anyone tries to tell you otherwise,
Call their bs and shame them until out of sight
 
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linksys

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If they are all synonymous, and their pharmacokinetics are the same; then why were they even given different names? For example, Wellbutrin has five other names, but they each have their own purpose. Zyban is used for smoking cessation, Wellbutrin for generalized depression, etc. Those are the only two usages I am aware of for that drug. There's also Aplenzin, Buproban, Budeprion, and Buproprion (generic). I'm not sure how those differ, though. Anyway, the point is that drugs should have TWO names: one trade name, and one generic. Not a whole sleuth of meaningless cognomens. A little regulation and enforcement could go a long way.
 

Digsbe

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If they are all synonymous, and their pharmacokinetics are the same; then why were they even given different names? For example, Wellbutrin has five other names, but they each have their own purpose. Zyban is used for smoking cessation, Wellbutrin for generalized depression, etc. Those are the only two usages I am aware of for that drug. There's also Aplenzin, Buproban, Budeprion, and Buproprion (generic). I'm not sure how those differ, though. Anyway, the point is that drugs should have TWO names: one trade name, and one generic. Not a whole sleuth of meaningless cognomens. A little regulation and enforcement could go a long way.
Relabeling with a new indication = more money on patent or new market.

Same thing with OTC Benadryl for allergies and Unisom for sleep. Both are just diphenhydramine relabeled for different indications.
 
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Caffeine QAM

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This is probably a dumb question, but shouldn't there be some kind of differentiating factor regulating the PROPER usage of thyroxine? For example, having unique uses for EACH brand name? Some discretion between Tirosint, Novothyrox, Levoxyl, Synthroid, Unithroid, Levothroid, and Levothyroxine would be nice...

Whenever I do a search regarding this issue, it always comes up with the same three disorders that t4 treats: hypothyroidism, hashimoto's, and goiter. What about broadening the treatment horizons for the utilization of each unique T4 medication?

Or is it all just a farcical hoax?
In the past they were not considered bioequivalent because of the lack of direct bioequivalency comparison studies to support the statement of bioequivalence. It's not so much that one brand is distinguished from another by any advantages or disadvantages, but rather that when a physician started a patient on a dose of a medication and titrates them up to a "stable" dose, switching it to another brand could cause them to receive a different amount of thyroid hormone and put them into hypo/hyperthyroid states.

As for why there are so many different brands, I'm sure I don't have the entire story, but each company could make money as long as physicians wrote for the thyroid hormone that they produce, since pharmacists couldn't substitute it with another brand - this isn't necessarily bad, since having multiple brands available ensures that there is some degree of competition and that no one company holds a monopoly on thyroid hormone. However, it does make it difficult for pharmacists and physicians to help their patients by trying to convert to a cheaper brand or something that's available.

Generic levotyhroxine exists - before, they were only be considered bioequivalent to specific brands (the generic companies produced the bioequivalency studies in order to get approval for the generic - I guess there weren't these studies comparing the brands to each other)...so you couldn't substitute Synthroid 100mcg with Mylan generic levothyroxine 100mcg for example, but you could substitute Mylan generic levothyroxine for Unithroid.

Looks like at least for levothyroxine, several products are considered therapeutically equivalent now, per the FDA:
http://www.fda.gov/downloads/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/UCM186430.pdf
So seems you can substitute Synthroid, Levoxyl, and Unithroid with the Mylan generic now, though it looks like you can't switch between Synthroid and Levoxyl (see page 11 Beioequivalence studies).
 

linksys

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In the past they were not considered bioequivalent because of the lack of direct bioequivalency comparison studies to support the statement of bioequivalence. It's not so much that one brand is distinguished from another by any advantages or disadvantages, but rather that when a physician started a patient on a dose of a medication and titrates them up to a "stable" dose, switching it to another brand could cause them to receive a different amount of thyroid hormone and put them into hypo/hyperthyroid states.

As for why there are so many different brands, I'm sure I don't have the entire story, but each company could make money as long as physicians wrote for the thyroid hormone that they produce, since pharmacists couldn't substitute it with another brand - this isn't necessarily bad, since having multiple brands available ensures that there is some degree of competition and that no one company holds a monopoly on thyroid hormone. However, it does make it difficult for pharmacists and physicians to help their patients by trying to convert to a cheaper brand or something that's available.

Generic levotyhroxine exists - before, they were only be considered bioequivalent to specific brands (the generic companies produced the bioequivalency studies in order to get approval for the generic - I guess there weren't these studies comparing the brands to each other)...so you couldn't substitute Synthroid 100mcg with Mylan generic levothyroxine 100mcg for example, but you could substitute Mylan generic levothyroxine for Unithroid.

Looks like at least for levothyroxine, several products are considered therapeutically equivalent now, per the FDA:
http://www.fda.gov/downloads/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/UCM186430.pdf
So seems you can substitute Synthroid, Levoxyl, and Unithroid with the Mylan generic now, though it looks like you can't switch between Synthroid and Levoxyl (see page 11 Beioequivalence studies).
Thanks for the info. Now I know why there are so many cognomens for virtually the same thing. It's all for marketing, and, like you said, to ensure that no one pharmaceutical company holds a monopoly. It's interesting that Mylan generic levothyroxine is bio equivalent to Unithroid, Levoxyl, and Synthroid, but Levoxyl cannot be substituted for Synthroid. Probably because, like you said, switching between brand names, after the dose has already been titrated to a stable dosage, would cause a different level of thyroglobulin to be in the body of the patient; thus yielding hypo/hyperthyroidism. However, with all said, I do still wish that there was some discretion between usages for different brand names. It would only make sense to have Novothyrox to be used for issues involving the thyroid as it relates to dental issues, as a theoretical example. (Novocaine). Another example might be that Mylan generic Levothyroxine could be used for issues involving impulse control. (Myelin, the lipoprotein present in the form of Schwann cells surrounding the axons of neurons, is responsible for impulsive behavior. The more myelin, as they say, the more rapid the impulse.)
 

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Thanks for the info. Now I know why there are so many cognomens for virtually the same thing. It's all for marketing, and, like you said, to ensure that no one pharmaceutical company holds a monopoly. It's interesting that Mylan generic levothyroxine is bio equivalent to Unithroid, Levoxyl, and Synthroid, but Levoxyl cannot be substituted for Synthroid. Probably because, like you said, switching between brand names, after the dose has already been titrated to a stable dosage, would cause a different level of thyroglobulin to be in the body of the patient; thus yielding hypo/hyperthyroidism. However, with all said, I do still wish that there was some discretion between usages for different brand names. It would only make sense to have Novothyrox to be used for issues involving the thyroid as it relates to dental issues, as a theoretical example. (Novocaine). Another example might be that Mylan generic Levothyroxine could be used for issues involving impulse control. (Myelin, the lipoprotein present in the form of Schwann cells surrounding the axons of neurons, is responsible for impulsive behavior. The more myelin, as they say, the more rapid the impulse.)
When it comes to bioequivalence, it's possible that A=B and B=C, but A =/= C...the reason for that is because statistical significance when comparing 2 products to each other cannot be extrapolated (i.e. via transitive property).
So even if Mylan and Synthroid can be interchanged and Synthroid and Levo-T can be interchanged, you can't interchange Mylan and Levo-T, because those 2 were not directly shown to be bioequivalent. The way statistics works is annoying, isn't it?

I think differentiating between brands by indication would not really help. If each product had its own specific indication, it's somewhat creating a monopoly effect. E.g. if Mylan generic was indicated for impulse control, then prescribers can only prescriber Mylan, so they'd have a monopoly on that indication. It benefits patients to have all of the products available for any indications - besides, pharmacologically speaking, there's really not much that makes one product different from another in terms of treating for any of the indications. Same strength and dosage form - the only difference is in bioequivalence. Plus, it would be a pain to remember which thyroid hormone is the proper one for each indication. Like, "this patient has hypothyroidism, whoops, wait I'm not supposed to use Synthroid, that one is only for Hashimoto's...which brand of levothyroxine is the one for hypothyroidism?". They all work the same, it's just a matter of figuring out the correct dosage.

Also the example I gave about Mylan being indicated specifically for impulse control while other brands are not is unrealistic because generics cannot have an indication different from what the brand product is approved for. Generics piggyback off of the studies on the brand named meds that got them their approvals for whatever indication. That's in part what allows generics to be cheap - they don't need to conduct their own studies, so it follows that generics can't have an indication that the brand doesn't have.
 
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linksys

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When it comes to bioequivalence, it's possible that A=B and B=C, but A =/= C...the reason for that is because statistical significance when comparing 2 products to each other cannot be extrapolated (i.e. via transitive property).
So even if Mylan and Synthroid can be interchanged and Synthroid and Levo-T can be interchanged, you can't interchange Mylan and Levo-T, because those 2 were not directly shown to be bioequivalent. The way statistics works is annoying, isn't it?

I think differentiating between brands by indication would not really help. If each product had its own specific indication, it's somewhat creating a monopoly effect. E.g. if Mylan generic was indicated for impulse control, then prescribers can only prescriber Mylan, so they'd have a monopoly on that indication. It benefits patients to have all of the products available for any indications - besides, pharmacologically speaking, there's really not much that makes one product different from another in terms of treating for any of the indications. Same strength and dosage form - the only difference is in bioequivalence. Plus, it would be a pain to remember which thyroid hormone is the proper one for each indication. Like, "this patient has hypothyroidism, whoops, wait I'm not supposed to use Synthroid, that one is only for Hashimoto's...which brand of levothyroxine is the one for hypothyroidism?". They all work the same, it's just a matter of figuring out the correct dosage.

Also the example I gave about Mylan being indicated specifically for impulse control while other brands are not is unrealistic because generics cannot have an indication different from what the brand product is approved for. Generics piggyback off of the studies on the brand named meds that got them their approvals for whatever indication. That's in part what allows generics to be cheap - they don't need to conduct their own studies, so it follows that generics can't have an indication that the brand doesn't have.
Well, you're very erudite on the subject matter. Good for you, man. I don't really have the time to just sit here and go back and forth on the topic, but you helped me see the subject in a new perspective. My gratitude. Peace, bro.
 

owlegrad

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Well, you're very erudite on the subject matter. Good for you, man. I don't really have the time to just sit here and go back and forth on the topic, but you helped me see the subject in a new perspective. My gratitude. Peace, bro.
Lol that is a pretty ungrateful way to show gratitude.

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linksys

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Lol that is a pretty ungrateful way to show gratitude.

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My mistake. I should have realized that some people on here are very sententious; not to mention full of themselves, like you. I will remember that in the future, and be careful not to mention the word "gratitude" for the sake of pompous asses like you.
 
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BidingMyTime

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have you ever seen levothyroxine 600mcg in tabs a day?! maybe more?
I've seen 500mcg/day, something rare genetically is going on for someone to need that high of a dose.

You got any cheap knockoff Rolex watches?
hotmail.com :lol :lol :lol :lol :lol :lol

This is probably a dumb question, but shouldn't there be some kind of differentiating factor regulating the PROPER usage of thyroxine? For example, having unique uses for EACH brand name? Some discretion between Tirosint, Novothyrox, Levoxyl, Synthroid, Unithroid, Levothroid, and Levothyroxine would be nice...
This is capitalism, once off patent, everyone can make their own version of any popular drug and give it its own name. Generally there isn't a lot of financial incentive to do this, but if it works, it works. Advil/Motrin is another great example of this.

Well, you're very erudite on the subject matter. Good for you, man. I don't really have the time to just sit here and go back and forth on the topic, but you helped me see the subject in a new perspective. My gratitude. Peace, bro.
Where did you get he was going "back and forth" with you, he was trying to answer your questions/concerns. If you didn't want an answer, why did you bother with all your long posts on the subject? This is a discussion board, if you aren't interested in discussing, then don't post. If you just want to pontificate your own opinion with no responses, than you should go get a blog or something.
 

swatchgirl

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Generic levotyhroxine exists - before, they were only be considered bioequivalent to specific brands (the generic companies produced the bioequivalency studies in order to get approval for the generic - I guess there weren't these studies comparing the brands to each other)...so you couldn't substitute Synthroid 100mcg with Mylan generic levothyroxine 100mcg for example, but you could substitute Mylan generic levothyroxine for Unithroid.

Looks like at least for levothyroxine, several products are considered therapeutically equivalent now, per the FDA:
http://www.fda.gov/downloads/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/UCM186430.pdf
So seems you can substitute Synthroid, Levoxyl, and Unithroid with the Mylan generic now, though it looks like you can't switch between Synthroid and Levoxyl (see page 11 Beioequivalence studies).
Is the Sandoz generic levothyroxine 100 mcg AB rated as well? Is it interchangeable with Unithroid 100 mcg? I could not find the Sandoz levothyroxine in the orange book.
 

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Is the Sandoz generic levothyroxine 100 mcg AB rated as well? Is it interchangeable with Unithroid 100 mcg? I could not find the Sandoz levothyroxine in the orange book.
That's interesting...you obviously consulted the correct source. I checked my distributor (McKesson) and they have the Sandoz levoythyroxine 100mcg listed as Orange Book Code AB2. Not sure why the actual orange book is missing that information. You might want to check your distributor as well.
 
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Sine Cura

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Copypasta:

Sandoz-labeled levothyroxine is actually Levo-T (same NDA). That is why you won't see it in the Orange Book or [email protected] because the databases list unique NDAs or ANDAs, not distinct NDCs.

Re-labeled presentations of brand drugs are not "A" rated to themselves (that wouldn't make any sense), like Actavis methylphenidate ER OROS.