Some patients won't substitute the branded drug for a generic, because it does not makes any effect. Why does this happens?
Why in some cases levothyroxine is not as effective as Synthroid?
Question posted by Solange319 on 14 Nov 2012
Last updated on 30 September 2019 by LaFloyd
The information on this page reflects personal experiences shared by our community members. It is not reviewed for medical accuracy and should not replace professional medical advice.
19 Answers
LaFloyd
30 Sep 2019
Years ago I encountered this difference between generic and Synthroid. I'm surprised to see that the discrepancy in performance still persists. Generics may work for some but probably not all. Be prepared to switch to Synthroid if the generic isn't getting the job done.
AbbyandSadiesMom
7 Feb 2019
When first diagnosed with hypothyroidism, I had a 30/day sample of Synthroid with much success. My initial paid script was the generic version; the side effects were horrible within two weeks. When the script was changed to "no substitute" my system returned to normal. Due to insurance cost issues, the script was again changed to the generic with the same negative side effects. My doctor marked the script "no substitute" and notified the insurance company that it was a medical necessity. I haven't had any bad side effects since taking the brand name Synthroid and my thyroid numbers have remained stable.
When I asked my doctor what the difference was, he stated that it could be something in the binding agent or a difference in the formulation of the brand name vs. the generic.
bbryson1
28 July 2018
I have been on Synthroid for 25 years with very little problems. My insurance sent me a letter that I should use the generic Levothyroxine so my doctor gave me a prescription. I took it for almost 3 months and started having heart palpitations. I went to my doctor and he did a EKG and blood work. My TSH was 15.37 so he changed my Levothyroxine from 112 mg to 137 mg. I have never had such an increase or decrease in my TSH in 25 years. Also, I could have had a heart attack and died just so the insurance company could save a few dollars. When I go back to my doctor, I am going to ask if he will put me back on synthroid.
Stpaulmercantile
13 Jan 2018
I’ve been on generic for several years and levothyroxine has not gotten my levels down to the normal zone. My doctor switched me to Synthroid, so we will retest in 3 months to see if it works better.
Generics are not always exact copies of the original drug. Generics are required to contain the same active ingredients, but the FDA allows results to vary 15-25% from the original drug. My doctor told me that the maker of Synthroid never patented the drug in the US. I verified this by googling Synthroid patent - zero US patents. His belief is that there was something about the ingredients and manufacturing process that was so proprietary that Synthroid believed nobody would be able to duplicate it. By not applying for a patent, they would never be required to reveal their exact recipe and manufacturing method. This is only a theory. I’ll update you in a few months to let you know if the real Synthroid worked for me.
Michellesy
7 May 2017
I have been on Synthroid for years. One time the pharmacy gave me Levothyroxine I never asked for it after about 2 months did not feel good at all. Went back on Synthroid, I felt much better. Now years later my insurance will not cover synthroid switched to Levothyroxine I am feeling terrible. Going to bite the bullet and just buy Synthroid between 50-60 bucks. It will be well worth it. I just can't handle the generic brand. good luck!!
wavedancer
11 April 2017
I learned that some of the fillers are lactose based and others pose a potential allergic reaction that can minimize the effects of the full dose causing inaccuracies. For me, it was an automatic weight gain and puffiness in the face, etc. I am a lean, fit person so this was very distressing.
nikoliatl
11 April 2017
I've been taking Levothyroxine since my thyroid was removed about 8 years ago, I've never loved it but its been OK and still seem to feel better than some on it. Recently my chemist was out of generic and gave me Synthroid instead which i was OK with because i've read it works really well for some, I've been on it two weeks and feel terrible, my brain feels like its miles away and I'm going thru the day on autopilot. Does it take a few weeks for a new brand to stabilize or should i be going to change back now?
AbbyandSadiesMom
7 Feb 2019
I would notify the doctor of the side effect. For me, it was the opposite. If side effects still present after a week but no more than two, that could be serious. Let your doctor know ASAP!
Trex0530
13 Feb 2017
I've been on thyroid replacement for over 12 years now and my doc and I have noticed a HUGE difference in the way they act. The biggest difference to me is that, while generic drugs are required to have the same active drug ingredients as the name brand in the same amount, it's the "inactive" ingredients that make the difference here.
I have found, and my doctor reached the same conclusion, that levothyroxine releases all of the TSH over a period of 6-8 hours, then you go 16-18 hours with no TSH. Synthroid releases it's TSH over a period of 16-18 hours so when it's reaching the period where it's not in your bloodstream any more, it's time for your next morning dose.
For this reason my mail order pharmacy fills all orders, generic or not, with name brand Synthroid. If the scrip is written for name brand only my co-pay is $85 for 90 days. If it allows generic substitute then it's $17 co-pay. I get the same bottle either way.
However, if I take it to a brick-and-morter version of the same pharmacy then I get generic levothyroxine.
Cinc880
17 Jan 2017
I too have been taking levothyroxine for years didn't feel good for years. I am now on Synthroid and it changed my life for the better.
pattycakes6962
30 Nov 2016
My doc decided to switch me from the generic to Synthroid just yesterday. I did not request or mention it. She thinks it will work better and not cause so much hair loss. I've been on the levo for 2 months. My numbers have improved but hair loss is troubling. Will report back after 2 months on the Synthroid! These forums are great!
wavedancer
30 Nov 2016
Thank you for your response. Having hit the tail end of menopause, I have already suffered hair volume loss and am not interested in experiencing any more of that! Also, I read that the generic has different fillers one can be allergic to as well as if you are prone to being lactose intolerant - not reccomened for substituting Synthroid for generic. I'm currently on Medical, and have to go to a new Dr., in which she will have require a medical necessity in order for me to get the Sytnthroid versus generic. Sigh, wish me luck, I will report back later this month.
abbellalove
17 Sep 2016
OK. I'm new here found this forum because I have stopped taking levothyroxine after it caused painful inflammation of my thyroid. I stopped going to see the doc for couple of months and decided to go see her. She blood tested me and said I had no thyroid activity and I told her that the levothyroxine had quit working and I was getting all the side effects :Moody, weight gain, and swollen thyroid. She wrote me a script for synthroid so I will be starting those tomorrow. I am happy to read that some of you have been feeling better with the synthroid. I believe that a body can build a resistance against some pharmaceuticals after detecting that they are synthetic. Levothyroxine worked for two years before it backfired so hopefully Synthroid will take care of me at least for a few years.
Abbellalove
fxa01
3 Oct 2016
I have no Thyroid activity and taking these drugs for over 10 yrs and found out two thing effect absorption. 1) Don't drink coffee up to 2 hrs after taking your pill. 2) Don't take any other pills (including multi vitamins) 2 hrs before or after.
Nikki192016
5 Oct 2016
I have been on synthroid for years. Several years ago I was switched to the generic and I was taking it. Don't know if you know this, but at one time, the generic was pulled off the market!! There were some problems with it. Now I felt more tired on it, and if I happened to miss a pill I was really tired. My physician told me, to stick with one medication, either all generic or all brand name. Everyone responds to different medications differently, if the generic works for you, fine, keep taking it. As my physician said, don't switch back and forth. If you feel better on Synthroid , then keep taking it. Yes, as that one person said it could be subjective, however, your energy level and your productivity can be, and if you don't feel good on one med, and do on another one, take the one that makes you feel better. I will never switch back to the generic.
TSMize8
15 Aug 2015
When I was first diagnosed with hypothyroidism, my dr prescribed Synthroid, and almost immediately I felt different. I had energy again, my mood was different, I no longer felt anxiety and constant tension, and I lost 30 pounds in 3 months without changing anything diet or exercise wise. I had zero problems maintaining my weight while on Synthroid (I'm a naturally thin person, so my weight gain was one thing that prompted me to have my thyroid checked to begin with.) Several years ago, my pharmacy automatically filled my prescription with Levoxythyroxine during a refill and I didn't catch it for a while. I didn't notice a difference in mood, energy, or weight gain so I continued to take the generic form.
The change was so gradual, it took me 4 years to pinpoint that the Levoxythyroxine had caused me to regain the weight, my energy levels plummeted, and my mood was back to constant anxiety and tension, like I wasn't even on medication. I have had so many life changes over the past 4 years (got married, had 2 babies, started my own business, and moved out out of state) that I chalked it all up to those things. My blood work always came back fine. Within the past 3 months, I finally pinpointed that the Levoxythyroxine was the problem and my dr switched me back to Synthroid. My mood and energy level changed almost instantaneous. It's too soon to tell with the weight gain/loss, but just the difference in the way I feel on Synthroid, I will never go back to taking generic. It just is not the same and does not work for me.
Inactive
4 April 2016
The FDA quality and purity standards are the same for brand name and generic drugs. I'm sure your Doc knows this, but chooses not to argue with you and keep you on the much less expensive generic Levothyroxine. Have you heard of the placebo effect? You probably think you are doing better with the Synthroid because you think it's better quality. You mention some changes but they are all subjective. You don't mention any blood test results. That would be objective evidence.
Your Dr. doesn't have a dog in this fight, so they will often go along with patient requests. They don't want to argue with you and want to keep you happy. That's the same reason you see so many expensive TV ads for prescription drugs. The money hungry drug manufacturers know that many Doc's will go along with a patient's request for a drug so they advertise them like crazy. I think advertising of prescription drugs should be banned. Whether or not you get a drug should be up to you and your doctor, not some marketing department.
TSMize8
5 April 2016
Do YOU have a "dog in this fight"? Or even a thyroid issue? You seem to be answering everyone's comments and telling them how they feel, soo I'm sensing your an expert on everyone and their issues? I did not experience a "placebo" effect, and yes my blood work was affected by the Levoxythyroxine. As I said in my previous post, I was on Levoxythyroxine for years before it started to have a negative effect on me. And, yes, I have done an immense amount of research on synthroid, levoxythyroxine, hyperthyroidism, ect.
Inactive
6 April 2016
No, I don't have a dog in this fight. My "dog in this fight" comment was meant to illustrate that doctors strongly prefer not to be arguing with their patients so if the patient requests a particular prescribed drug and the Dr. knows a generic equivalent is available at much lower cost, they will avoid an argument and not risk ticking off their patient. They will prescribe the more costly name brand, knowing there will be "no harm" (except to someone's wallet). I simply offered my researched information in a good natured attempt to save other folks some money.
Yes, I do have hypothyroidism, and have been on 75 micrograms of Levothyroxine for about 5 years at age 71. Read my original post, it's thoughtful, reasoned and even toned. Your response sound like you might have been having a bad day, so hope things get better for you:-)
Inactive
6 April 2016
BTW, just after posting my earlier reply, I noticed you are talking about "Levoxythyroxine" and you spell it exactly that way three times in your post. You sound like you really know what you are talking about, so we must be talking about two different drugs. Your drug would have an extra oxygen. I'm talking about Levothyroxine. Pardon me for being a stickler on chemical and drug names but I can't help it because I'm a chemist.
Paco51
3 June 2016
My endocrinologist insists that in this case only, that Synthroid should only be used as opposed to generic. His nurse practitioner (who has Hashimotos as well) says she has tried generic but had to go back to Synthroid.
As a health care practitioner myself, I am strongly pro-generic in all cases, but I am going to take their advise and go back to the name brand in this case and see if my symptoms improve.
Mam512
26 July 2016
My doctor told me to only use synthroid. Levothyroxine is sent to the pharmacy by many different drug companies which will all have a different potency which will change your levels frequently. Synthroid will stay consistent and for those of us that have sensitive levels we shouldn't play with them to save a few bucks. My doctor did not care about the drug companies. She was more concerned about my health. She left the practice and I was talked into going to levothyroxine. It was a nightmare. It makes a very big difference. The FDA can regulate away but they have nothing to do with how your body reacts to medication. Synthroid is the better choice all the way around in my opinion.
debussy
15 Aug 2016
Realize I'm late to this thread and may have missed the mention, but my doc prefers synthroid because she said it's the fillers or carriers sometimes used in the generics that might inhibit absorption. I'm on synthroid but just changed insurance and am trying the generic... hoping it works as well because it is substantially cheaper.
nurseryn
5 Sep 2016
@TSMize8
1-There is no drug called Levoxythyroxine. We are all left to assume you're talking about Levothyroxine, the generic for Synthroid. Otherwise you're talking about some other drug that you're misspelling.
2-Generic can have a difference in amount that is absorbed, however, this will be evident through bloodwork, it is a negative feedback loop that is very reliable.
3-"My blood work always came back fine." If you're TSH was WNL then your symptoms were not caused by your generic Levothyroxine. Your doctor could have tried synthetic T3 to see if that helped, but I would have added a depression screening, as those are classic presenting symptoms and you're at higher risk for post-partum, you moved, and you're stressed.
4-"My mood and energy level changed almost instantaneous"- this is a placebo effect. The medication takes 4-8 weeks to have any subjective or measurable objective signs/symptoms.
5-I am a provider AND hypothyroid, so I have experience from both sides.
Maybe someone found some tidbit of insight in your post, but mostly your comment is confusing and provides incorrect information.
Inactive
5 Sep 2016
Nurseryn has posted the most thoughtful and well informed info on this thread. Given that Levothyroxine has the exact same active ingredient as the name brand Synthroid, the thing you should do in seeking the much less costly generic is to take it and have blood work done until the desired level is achieved. It may be possible that the absorbtion rate of the two are somewhat different, but you should be able to achieve the desired blood results given appropriate dosage adjustments.
I have been taking generic Levothyroxine for over 5 years at a very low cost of about $3.33 per month from Walmart mail order pharmacy in Texas. I am happy. Anyone who wants to pay far more for Synthroid is free to do so but I don't understand why they'd want to waste the money.
BethSJ
17 Sep 2016
Possibly because it's the right thing for them?? Headaches went away almost immediately after switching to the brand drug. Every body is different and drug reactions vary. Ease up.
ittybittykitty
4 Oct 2016
For what it's worth, post-diagnosis I was on levothyroxine for several years, slowly increasing the dosage, while my symptoms continued to get worse and new ones kept cropping up. I switched to a new endocrinologist, who told me that MANY people don't get the proper effect from the generic, and switched me to Synthroid, while also increasing my dosage - and magically, THINGS GOT BETTER.
Fast forward a few years, and I'm talking to my PCP, who has taken over maintenance management of my thyroid meds, and I said I never knew whether it was getting me up to the right dosage or switching me to the name brand that made all the difference, so we decided to switch me back to the generic, same dosage, and see how I did with that.
Well, it's been a few months, and I've just not been feeling great, and have been having some new symptoms too. I once again reviewed the list of hypothyroidism symptoms, and sure enough, came up with a list of about 20 symptoms I've been experiencing the past few months, some of which I never had before and didn't realize were thyroid related.
Soooooo I'm pretty sure it was the switch back to the generic that caused this. Having it confirmed with blood work and switching back to Synthroid tomorrow.
ittybittykitty
4 Oct 2016
Oh, and also for what it's worth, my mother in law takes the name brand Synthroid, and said for her (and according to her doctor) it was because she had a bad reaction to the coating on the generic levothyroxine, more than it was the problem with the generic vs. name brand levothyroxine. So there may be multiple reasons why someone could do well on Synthroid but not the generic.
wavedancer
3 Nov 2016
I am in complete alignment with the above statement. I was diagnosed with Hypothyroidism due to suffering a surprise supreme lack of balance (which actually led me to my first Endo Specialist), at 24 years old (6 years post my first pregnancy). After a series of physical accidents (ie) dropping plates in my hand for no reason, running into walls while looking straight ahead, losing my balance in the shower while rinsing my hair (closing my eyes), riding my bike along the beach and misjudging the lane and falling down the embankment, falling off my roller skates while standing still, that finally led me to a concussion, and therefore led me to an MRI/& my first Endo specialist.
That's 30+ years ago. My Endo believed it was related to the pregnancy (which upon research can be a true variable). Not only was I naturally a fit athlete and of small bone structure, prior, but now it was a supreme effort to take a flight of stairs, and not feel rested after 18 hours of bed rest. Wait, what?! I was 18! There were an additional 30 pounds added almost overnight. In fact, if seemed that if I even looked at food, I gained weight. Hair volume loss and eyebrow loss confirmed.
I was put on Synthroid starting at .25 and we experimented with increasing dosage for 9 months until I felt “right”. I lost 4 clothes sizes, regained my balance, my mind, and my sports activities. He told to never vary my Synthroid RX for generic. EVER. I have varied dosage only from 125mcg to 150mcg (as “normal” for me) during my lifetime and through menopause.
Throughout my lifetime I have had to switch doctors due to moving around the planet. Once of those times was Europe, where I came to meet Dr., Sir Richard Bayliss, a renowned Endo specialist who reconfirmed I should never vary from Synthroid. I went to him at 38, because I was seeing some symptoms return. Turns out I had a B12 deficiency as well, known as “Lack of Intrinsic Factor”, (meaning lacking the gene/inability to absorb B12 from food or vitamins). The symptoms were very similar and mirrored Hypothyroidism. I was learning tennis at the time, and could not “see” what was happening on the left side of the racket. It was like a black elevator hole. Missed the ball 100%. Sir Richard Bayliss, insisted that I stay with the Synthroid, and added monthly B12 injections to halt the disease that he said was hereditary (that I had no prior family history knowledge of), and had dire consequences otherwise.
Lack of Intrinsic Factor affects the spinal cord, slowly eating it up/eventual paralysis as well as a variety of other cancers. YAY!
I inject B12 1 x a month and am certain messing with my Synthroid dose would have adverse effect should I decide to become a personal scientist where my chemistry is concerned.
I am a confirmed champion of not messing with what is working no matter what the current issues are saying are safe to experiment with. Everyone’s body chemistry is different. It's up to each individual to manage your own care and say what you mean and enforce it with your health care professionals.
diwash03
28 Jan 2017
I had the exact same experience with switching from pure thyroid to generic. I felt like I was losing my mind. It felt like I was not taking any thyroid when I went to the generic brand. Now I have to pay an arm and a leg for these life sustaining meds.
mrscem
29 Jan 2017
Thank you for sharing. I thought I was losing my mind this past year and when I read your account, I, too, had the exact same experience. Regrettably my endocrinologist died several years ago; so I figured I'd been stable for 20 years, with cancer recurrence at this point, I'll have my primary prescribe the medication. Well, Express Scripts substituted generic without my knowledge and it was a year before I realized what happened. Synthroid was in parenthesis and in the smallest print on the side of the label it said this is a generic substitute. In the meantime, I was having symptoms of hypothyroidism and all the while thinking I was losing my mind. My primary said my labs were normal, but I was far from normal and could barely get through my day, gained 30 lbs, sleep issues, very depressed, muscles were so weak I could hardly walk without stopping to rest.
Thankfully, my husband is a doctor and I was finally able to convince him to give me a prescription of Synthroid with "Do Not Substitute" as he didn't recognized the woman he had married over 30 years ago. Then the pharmacy couldn't get the insurance to approve the brand name; long story short, ExpressScrips finally agreed to a therapy change over ride but will only dispense 30 pills at a time and of course my co-p is higher but I finally got my life back. Thanks for allowing me to share.
Susers
6 Dec 2017
This is good news. I am going to switch. I have been on Levo 3 months 75 mcg and gained 7 lbs. Numbers great, me, not so much. Going to switch to 50 mcg Synthroid most likely. What do you think?
rainygirl11
18 May 2018
My husband was diagnosed with Hashimoto’s many years ago. He has tried Armour Thyroid, Synthroid, and the generic version of Synthroid. His symptoms rarely subside and his mood usually gets worse. He is very thin, has lost the hair on his legs and arms, has no appetite, is tired most of the time, and his moods are like a roller coaster. He finds more relief from Reishi mushrooms, kelp supplements, and tea made from stinging nettle than he does from the pills. He is 63. Any thoughts on why he doesn’t gain weight although he has hypothyroidism? The pills make him feel and act like he’s on speed. A former doctor even asked him if he uses cocaine! Nope, just the pill you prescribed, doc. The most recent doctor said that his thyroid isn’t working at all. Yet he hasn’t had a pill for weeks, just the natural things I listed.
msdebbie64
13 Nov 2014
Are you saying the generic is not as efficent as the brand name?
4N Substances
13 Dec 2012
Wow, after reading these replies I think
I'll try to insist on Synthroid. Knowing the Insurance providers, it will probaby require a letter from my MD to get the real thing, right? I've felt for a while my symptoms were not well controlled-this could be why! I'm often cold when no one else is and my hair falls out-a lot! My blood tests are always in normal range, however. I've read that one must be insistent in requesting a dosage change if one's health care provider doesn't acknowledge that tests don't always tell the whole story with hypothyroidism. Is there a good alternative to Synthroid or is about the only game in town?
You guys are all the best!! Love knowing the Community is always here for me. :))
endlessPred
15 Dec 2012
Tell your doctor and say you don't want the generic. He can document you are having problems and will have that on file if there is an insurance problem. I am on Medicare and they take label as that is what my doctor prescribes. No problem switching from generic. Often the switch is done at the pharmacy level because insurance says to use generic for a cost advantage. The pharmacy is saving you money and may or may not discuss the change. Mine immediately redid the prescription and no problem. So it probably won't take a letter, but get it into your chart.
endlessPred
15 Dec 2012
And it is the only game in town unless you use Armour synthroid. My docs here feel it is unsafe because of mad cow and swine disease. They also say each batch is different and can cause too many disruptions. Because mine changes a lot, it would not work for me. And I know enough about prions to stay away from that possibility.
joenolan1
14 Nov 2015
With the symptoms you describe of being cold and hair falling out, you might want to discuss Wilsons temperature syndrome with your doctor and the use of the WT3 protocol.
CDick724
9 April 2018
Synthroid isn’t the only brand name option. There is Levoxyl, Levothroid, Unithroid, and Tirosint.
smileyhappy
15 Nov 2012
Hi Solange,
I only get Synthroid myself. I don't take a chance with the Generic in this case since I think we go through enough of up and downs with our Thyroids we don't need any other problems.
mjpatton
4 Oct 2015
But isn't synthroid very expensive? My insurance will not pay for synthroid at all so I must pay over $100 for a 90 day supply. Any ideas how I can get it cheaper. My Dr. has already communicated with my insurance company but they won't budge.
shannoncpht
7 Oct 2015
Try Synthroid Direct program. No more than $25 a month directly from manufacturer. Your doctor should have form or you can google it.
skstiles612
10 Oct 2015
They put me on the generic for a year. I saved nothing. It was like I had taken nothing for a year and caused me to end up having five eye surgeries. The cost was almost my vision. My prescription says no substitutes
TSMize8
16 Aug 2016
You might double check with your insurance. If it is "medically necessary" then they may cover it. It could be as simple as your Dr writing that on the prescription!
bethbenny
25 June 2018
I am retired but I have taken Synthroid for the past 22 years. I pay 13.00 for a 1 month supply. When I was working I paid about 30.00-35.00 per month, for the same supply. I was once told by my endocrinologist to never change from Synthroid. I have kept that but I don't know much about the difference.
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