Thyroid UK
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Generic vs. Brand Levothyroxine

I have hypothyroidism and have been taking the medication available on the NHS. Anyway, my sister also has hypothyroidism and has for 15 years, but she lives in Los Angeles and she takes Synthroid. She has stressed to me on several occasions the importance of taking a named brand over a generic because of the quality control/consistency/reliability of it to keep the TSH level as stable as possible. She said this has been stressed to her many times by her Endo in LA. I also just spoke with a person in the US who also has hypothyroidism and is currently taking Synthroid. She said that when she tried a generic a couple years ago, her TSH level became unstable and she quickly switched back to Synthroid. They are both doing well while I just don't feel all that well. I am tired all the time I still have symptoms when taking Mercury or Almus brands.

After reading many comments on this forum, it appears to me that generic products made by mercury and almus/actavis in the UK are inferior, possibly very inferior to the point of causing health problems and complications that wouldn't be prevalent on a branded name. Generally speaking I am fine with generic versions of products such as ibuprofin or cold medicines, but one thing I do have a problem with is QC/Quality Control and it seems to me there is a real lack of concern regarding the quality control of Levo in the UK. I even went to the pharmacist to make a simple request to get the same generic brand every month and they said that could be difficult to do... and my immediate though was.. WHAT! Are you kidding me??? You can't even provide a same generic Levo every month??? To me this just shows the lack of concern over this medical condition and the seemingly lack of understanding regarding continuity, quality control and consistency of dose. I mean really, take 100 mcg of Almus, 25 mcg of Mercury? Who thought of that brilliant plan?

The idea that one generic is the same as the next is ridiculous, they just aren't. There is variability in the potency of each brand. Even each batch can vary in strength. Put that together with generic pharma companies making the cheapest products they can and using multiple sites in foreign countries to manufacture it and you get a recipe for inconsistency and varying amounts of micrograms you take in daily, regardless of what the package says you are taking. Different brands supplying me with Levo every month, which are manufactured where? How many manufacturing sites to they have? Where are the manufacturing sites located? Is the Mercury Levo I get this month manufactured in the same place as the Mercury Levo I took last month (that does make a difference, it might as well be a different brand).

All I can see is a future of dealing with sub-par medication that may have a considerable affect on my overall health and energy levels and frankly I'm really not happy about it. I asked my GP if brand names were available and he said no. Well, fine. The NHS doesn't want to pay the money. But does that mean I am unable to get any alternative to the generic levo being offered? Is is possible to get a prescription for Synthroid or another name brand if I am willing to pay for the prescription? Frankly I believe this generic Levo is far inferior to a branded product and I am at the point where I don't want it. How can I go about getting a brand name prescribed to me if I am willing to pay for it?

15 Replies

You're preaching to the converted in the main. Change your pharmacist if he won't agree to supply you the same generic every month. You may have to wait a day while they reorder if they don't have the generic you require in stock.

Ask your GP for a private prescription for Synthroid. If s/he won't agree buy online without a scrip..

PM me if you need a supplier.


Hi Clutter , I am not sure how to private message , but I am interested about Synthoid , could you give me as much info as possible please. Than you very much. Marja


If I were going to get a USA product, I'd go for Unithroid or Lannett (same thing).

You can use a standard UK NHS levothyroxine prescription to purchase levothyroxine from many non-UK sources. Might have to photograph it, or scan it. And you will have to pay!

I have taken two German products, Aliud and Henning (now Sanofi Deutschland) levothyroxine products. Was happy on both when I had not been happy on Actavis, MercuryPharma, or Actavis AND MercuryPharma.

(Am currently OK on Actavis plus Uni-Pharma. Oddly.)

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I have had Eltroxin for 27 years until lots of smaller companies merged and now it is Mercury Pharma or AMCO? Who knows! Any way since that happened months ago I noticed I didn't feel so good and like you I started to get different Levo's and insisted that I had Eltroxin (my pharmacy did their best) I managed to get Eltroxin 100 but had to have 25 of Levo MP as they stopped making those. During this time I think ( but don't know) that the Eltroxin also became generic. I really didn't feel good at all, I was having symtoms I hadn't had for years.On my last script MP had stopped making Eltroxin so I have completely changed to Activis Levo as my pharmacy say they can reliably get that. I take the same dose as with Eltroxin 100/125 alternate and have been on them for a week now and at the moment I think I feel fine. I feel a bit funny sometimes but I have travelled to Australia to see our family for four weeks and it is 42 degrees so maybe it is the heat. I have 2 months supply of Activis so will have a good idea by the time I get home how it is going, if it's not working for me by then I too will be asking for a brand or may have to get it and pay for it. I am just amazed how we all get treated on the "amazing" NHS. It is discusting so many people are battling with substandard Meds. I did actually Yellow Card MP because like you I didn't think their tablets wear stable form one pack to another. Best wishes, Kathy x



I'm not replying via PM so that other posters can correct any errors I might mke.

If your GP won't test for autoimmune antibodies you can be tested privately via Genova or Blue Horizon details of which are on the main TUK site.

Treatment for Hashimoto's is the same for hypothyroidism without autoimmune disease but having one AID can mean you are prone to other AID.

GPs have a wide but shallow knowledge of disease and most have very little knowledge of thyroid disease. Unfortunately, endocrinologists are not much better as they are inclined to be diabetes specialists with thyroid tagged on.

Recovery and achievement of 'wellness' is a slow process. The serum result isnt the same as the intracellular metabolism of levo, the latter following by several weeks/months in my experience. Hence the value of keeping a diary. Your increase from 50mcg to 100mcg may have been too much to cope with in one go. You might have been more comfortable increasing to 75mcg and raising to 100mcg two/three weeks after.

If you continue reading & researching you'll find that most experienced 'roidies wil disagree with your GP on a number of issues:

1. Treatment should be by symptoms NOT by TSH range which may not be your optimum TSH level. You can determine your optimum TSH by keeping a diary of symptoms related to dose increases/decreases/generic/brand changes etc.

2. There is anecdotal evidence that diet is important and that all autoimmune issues start in the gut ie absorption issues often caused by gluten intolerance. Many 'roidies are gluten intolerant even if not coeliac. Many also feel better cutting out gluten, sugar, dairy and eggs and advocate following a 'paleo' diet.

3. There is great dissatisfaction with the quality of generic levothyroxine and T4 monotherapy as a protocol. Those who are unable to persuade their GPs to prescribe branded levo, T3 &/or NDT resort to buying online or buying from countries which sell OTC; France, Greece, Cyprus, Thailand to name a few.

4. Ferritin, vitD, B12 and folate are often deficient in hypothyroid patients and are necessary for optimal absortion of levo. If you can persuade your GP to test these you will probably find yourself to be deficient, in which case prescriptions should be given to resolve, or you'll be low in range and will need to self supplement. VitC, B complex, magnesium and zinc supplements can also be beneficial.

Finally, sleep is very important. 10+ hours should be the aim and a daytime nap might still be required.


You might be surprised how many USA sufferers say that Synthroid (specifically) was one of the worst thyroid hormone medicines they have ever taken. I think the favoured USA brand is Unithroid which is actually also sold as a generic there!

In the UK context, I generally make no issue of people calling our products "generic" but, really, it is our prescribing that is generic: GP writes "levothyroxine". No-one gets a product that is anything but one of the three currently available products - all of which are fully branded and liveried. (Only rarely do people get them "loose" rather than blister packed.) The nearest to any generic are the Almus and Lloyds packaging of the Actavis product.

Switching simply to get required dose or because the pharmacy is unhelpful is a really bad thing.


It is my understanding that all three of the levothyroxine products available are generic products. Generic meaning the drug is no longer under patent and can be manufactured under some other name than the original. Generic isn't a bad term, generally speaking, it just means a biosimilar. I don't know the history of Levothyroxine because it does go back to the '50's, but I am pretty sure that Synthroid was the first product of this type. I don't really know the history of other "branded" products which seem to be well known. I do know this though, the acceptable variance range for US Levo products is more strict than it is in England. I also know that price is the driving factor for the products being offered on the NHS for hypothyroidism. I also believe that branded products have more of a reason to protect their brand by putting out a top quality product.

The fact that Synthroid was singled out as a problem drug doesn't surprise me primarily because of the numbers of people taking it. I think having a discussion about taking T4 only is a good one and has merit, but comparing Synthroid to a generic product like MP is pretty easy.

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Levothyroxine has not been in patent for at least decades (not actually sure whether it was ever patented here - never was in the USA, I read). You are quite right, Synthroid was the first synthetic levothyroxine product - in 1958.

The range of potency allowed in the USA is 95 to 105% whereas in the UK it is 90 to 105%. However, because this is the laboratory measurement of levothyroxine content it does not necessarily represent what the tablets can deliver - which was the issue with Teva's products that resulted in their withdrawal. I strongly suspect that the amount of levothyroxine in each tablet is actually very well controlled in this laboratory sense - at least so long as reasonable care is taken over storage.

Synthroid has a significant issue which is that it is coloured (except the 50 mcg tablets). The agents used have been claimed to cause all sorts of effects. As none of the UK products are coloured I really have not taken much notice of the issues.

When all USA levothyroxine tablets had to apply for approval as new products a number of years ago, Synthroid could not even make sure they were the first to be approved! So theirs is not the USA reference product.

The USA number 2 brand Levoxyl has been totally off the market for an extended period. Another significant USA brand - Levothroid - seems to have been withdrawn entirely as they cannot satisfy the requirements of the FDA.

One of the now-unacceptable practices of the USA levothyroxine manufacturers was to use overage. That is, put in a bit too much on purpose on the basis that by the time a patient takes it, some will have degraded. It is now required that all manufacturers (here and there) target 100% potency.

The past couple of years has seen activity in the UK in terms of regulation and revision of standards. At least some of the issues might well have been due to various tweaks to formulations in order to keep the products legal.



Have a look here:


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I think you make a great point I'm in my 30s and have hypothyroidism. I startes feelkng the symptoms coming back and couldn't work out why until I read an article about mixing brands. I'm was on 150mcg levothyroxine and on two different brands, I spoke to my doctor who hadn't heard of this but read up on it. It turns out the article and you are right. Iam now on one brand and feeling great my pharmacist promise to get the same brand for me. Seems like you need to have an understanding doc. Good luck xx

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You can buy levothyroxine (synthroid) here without a previous prescription (the online consultation is easy) <site deleted>

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I don't know if it applies to levothyroxine, but many generics are not made by identical processes to the original patented medicine. As a result, even though the active ingredient is the same, in theory anyway, biproducts, and the fillers and other adjuncts are not the same.

This shouldn't be a problem, but then we should all feel well when our TSH is in range....


Can u still not get Synthroid in the uk from our GP? And if so why can’t we? And why is everything here in the uk generic and not branded?



No - branded Synthroid levothyroxine is not, and never has been, available in the UK.

The fundamental reason is that no-one has ever successfully applied for a product licence to allow its supply. I do not know if anyone ever applied at all, but I suspect not.

Technically, Mercury Pharma's Eltroxin is not a generic.

Why would we be keen on getting Synthroid?

Note: This is a four-year-old thread. Possibly not the best place to raise questions.


This was the post I found when doing a search on google. After reading a Facebook post. They where talking about Synthroid. I just couldn’t understand why we couldn’t get this in the uk. I was told I was taking a generic and not a brand. And couldn’t get a brand while in the uk either. It’s all a little confusing to me



People in the USA go on about Synthroid - and a few other countries where it is available. In my time reading around, I've seen many, many people prefer one of the other makes of levothyroxine.

Sometimes "generic" (i.e. non-brand) is seen to be anonymous tablets in an anonymous bottle and changing every time they are dispensed. All four UK makes are very clearly labelled and packed with their own Patient Information Leaflets. Most of us manage to stick to the same make every time by discussing with the pharmacies, and wandering round different pharmacies, if needed. I very strongly recommend not switching makes once you have found the best for you.

There is absolutely nothing magical, or even special, about Synthroid. Except its marketing budget.

And it works both ways. People in the USA cannot get any of the four products we get! All of which are described here:

More information about Synthroid here:


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