Euthyrox and Brain Fog: What Users Say

• And...
• March 11, 2021

For Underactive Thyroid "I was taking Levothyroxine 88mg from Walgreens or CVS since I was 18. Now I’m 33. Switched pharmacies to a neighborhood Walmart because it was closer to home back in Sept 2020. They gave me a generic called Euthyrox and said it was the exact same thing, so I trusted them. They just said the packaging was different. They were so wrong! Since September 2020, I’ve been having horrible side effects - muscle aches, pains, and stiffness all the time! Muscle weakness, blurred vision, chest pains, severe acid reflux (GERD-like symptoms). Foggy brain, forgetfulness, and feeling cold all the time. Didn't feel like myself at all! I almost passed out twice last week and had enough! I went to the Dr and she immediately switched me back to my meds from before. Today will be 6 days that I have switched back and my side effects have been subsiding. It was so scary and still is knowing this medication is out there! Please don’t take it. When I almost fainted and had chest pains, that was the scariest part for me."

• joy...
• Taken for less than 1 month
• February 10, 2021

For Underactive Thyroid "In November 2020, I was diagnosed with low thyroid. My doctor put me on levothyroxine 25 mcg. I also went to Walmart and they gave me Euthyrox. I started taking it on the 11th. After taking it for one week, I began having hip pains that radiated into my legs. My joints ached and burned. I had headaches, low energy, dizziness, confusion, and a foggy brain. I didn't want to move as it hurt. I am a retired nurse and knew the recent change was due to medication. I stopped taking it on the 19th of November. I went to the doctor's office and was told to stop taking it. By Thanksgiving, I was feeling better. It took a few weeks to feel normal again. I have been prescribed Synthroid today and going to try it. It is the brand name of levothyroxine. Hopefully, I can use it. They need to inform people about how dangerous this medication is. I will stop using Walmart. They told me I was sick with a virus and treated me like I was delusional or making it up. I hope they never experience the same as I did."

• Geo...
• Taken for 1 to 6 months
• October 12, 2020

For Underactive Thyroid "Began taking in early June when Walmart pharmacy refilled my prescription, saying Euthyrox was their new generic and what I would be getting going forward. Within days of taking the first pill, I began to experience headaches that progressively increased in duration and frequency during the four months of taking Euthyrox. Then began the insomnia, tinnitus, heat intolerance, uncontrollable sweating, swelling in the face and eyelids, diarrhea, neck and shoulder pain, blurred vision, fatigue, occasional dizziness, dry mouth, loss of appetite, and brain fog. Stopped Euthyrox almost two weeks ago, and most symptoms have gone away except for headaches and neck pain. Definitely returning to the prior medication, this one was disabling."

• Bee...
• Taken for less than 1 month
• September 1, 2020

For Hashimoto's disease "I was switched to Euthyrox by the pharmacist at Walmart and did not notice until I got home. I called the pharmacy and asked about the drug, and was told it was the same medication, just another brand. It is not. The first day I took it I had a migraine headache and shortness of breath. I thought it was just me, so I went on and stayed on the medication for 2 weeks, thinking my symptoms would improve. They got worse. By the time I was 2 weeks into taking this medication, I could barely get out of bed. It was like being in a fog all the time, with absolutely no relief. I called back and spoke to the pharmacist, this time getting a different person. He told me that my doctor could specify Synthroid and they would make sure to keep it in stock. I messaged my endocrinologist and he quickly sent in the prescription specifying Synthroid only. I am already feeling better. Please do NOT take this medication."

• Gay...
• October 21, 2020

For Underactive Thyroid "Horrible drug. Almost landed in ER. Been taking Levothyroxine, generic for Synthroid, for years, a little yellow oval pill with no issues. Called for a refill at Walmart. Arrived home to find boxes of blister packs. Definitely not my normal pills, which came in a pill bottle. Called Walmart and asked about this drug Euthyrox by Merck in Germany. Person who answered the phone said exactly the same, no worries. HE WAS WRONG. Didn't put 2 & 2 together for over 3 weeks as I became sicker, my side effect symptoms were brain fog, strange headache all day, every day, dizzy, heavy pulse in my neck, sudden heatwaves, unsteady on my feet, vision weird, and exhausted. Figured out it was due to changing to this manufacturer. Many reviews from people who experienced the same side effects after Walmart changed to this manufacturer. Walmart should have said something. Doctor gave me a prescription for the old Levo. Immediately stopped taking Euthyrox. Today is the 4th day back on the old pills. 90% better. Called Walmart Corp. & FDA. NOT LIKE OTHER GENERIC LEVOTHYROXINE."

• Bob...
• Taken for 1 to 6 months
• October 22, 2020

For Underactive Thyroid "Walmart switched my levothyroxine medicine without doctor permission. I started taking Euthyrox in May, started having sharp pain, muscle spasm, headache, dry mouth etc. The pain became unbearable. Went to the doctor and had inflammation, high sodium, kidney function decrease, and pain all over. I couldn’t focus as I had brain fog. This medicine should not be sold. Walmart is trying to save a dollars while putting our lives at risk."

• Can...
• Taken for less than 1 month
• October 30, 2020

For Underactive Thyroid "I had my Levothyroxine prescription refilled at Walmart like 3 weeks ago, and they gave me Euthyrox, saying that it was a new presentation. They said they had changed the name, but it was the same medication. I’ve been having lots of headaches, itchy skin, dry mouth, and loss of focus. I thought I had an allergic reaction to something, but I haven’t changed anything-soap, detergent, lotion, anything. My husband told me it could be the new pills, and now that I read all the comments, I realized that is my problem."

• Jen...
• Taken for 1 to 6 months
• June 9, 2021

For Hashimoto's disease "I've been on Levothyroxine for over 10 years and haven't had any issues. All my levels have been great. Wal-Mart pharmacy prescribed Euthyrox in place of my Levothyroxine, stating it was the same, and it is NOT THE SAME!! After two months of missed periods, weight gain, brain fog, moodiness, depression, etc., and now my blood work has CONFIRMED my levels are all off balance for the first time in over 10 years!!! DO NOT TAKE THIS MEDICINE!! Wal-Mart, please STOP using this!! My Dr. has switched my prescription to Walgreen's, and I am now back on Levothyroxine once again and throwing Euthyrox in the TRASH!! Beware, it is not the same, and you will be messed up!! Euthyrox should be removed, and I am reporting it everywhere I can report it!!"

• Sco...
• Taken for 1 to 6 months
• November 7, 2020

For Hypothyroidism, After Thyroid Removal "I am so glad I came on here to look at reviews for this medication, Euthyrox. I have had horrible headaches, dry mouth, brain fog, dizziness, muscle pain, tinnitus, and neck aches. I went to see my ENT because I thought I had something seriously wrong with me. He is scheduling me to have a CAT scan done. I'm going to tell my endocrinologist about my issues with this medication. Getting off this one and see if my issues subside. I was on a different generic med, but Wal-Mart switched me to this one. Shame on them!"

• LoL...
• Taken for less than 1 month
• October 23, 2020

For Hashimoto's disease "I have had Hashimoto's for 8 years. Tried Levoxyl, Synthroid, Armour thyroid. Finally went to generic since they all seemed about the same and the cost was far less. I felt great, very stable TSH, etc. Walmart switched to Euthrox with my last refill, and I feel absolutely horrible. Low energy, weight gain, complete brain fog, and many, many more. Since it was a new med, I alternated it every other day with my old generic and this. Felt okay, so I switched to Euthrox daily and honestly feel as if I am taking NOTHING. Glad to hear it seems to be an almost universal complaint. I plan on visiting Walmart tomorrow to see if there is anything they can do about replacing this horrible medication."

• Ang...
• Taken for 1 to 6 months
• July 27, 2020

For Hypothyroidism, After Thyroid Removal "I have taken levothyroxine for years, usually Sandoz. My pharmacist changed my script to Euthyrox 2 months ago. I noticed the last 2 weeks my head is in a fog, want to sleep more than usual. I’m very disappointed and will talk to my dr about this."

• Tha...
• Taken for 1 to 6 months
• November 3, 2020

For Hashimoto's disease "I was on Levothyroxine for three years. Three months ago, Walmart (without permission) changed my prescription to Euthyrox. At the time, I didn't think it would matter, so I took it as I had my previous med. I started having leg and hip pain - then extreme brain fog - tingling and numb extremities - depression. I went to the doctor and was told my levels were within range. The doctor stated he had not heard of Euthyrox. Nothing has changed in my life (other than COVID), but the med. I called Walmart, and they told me they could no longer get Levothyroxine. The pharmacist explained that Euthyrox was much better in foil packs and would not lose its purpose as Levothyroxine would once it was open. After reading other comments, I'm switching back and to another pharmacy."

• Vee...
• Taken for 1 to 2 years
• July 21, 2021

For Underactive Thyroid "Was on generic levothyroxine for several years, then last year got switched to Euthyrox. Almost immediately started feeling awful. Nausea, shortness of breath, fatigue, headache, brain fog. My doctor couldn't explain why I was having issues. Reading similar reviews makes me realize it's not just me. I will have to find a better alternative because I can't function like this."

• Dus...
• Taken for 2 to 5 years
• July 10, 2022

For Underactive Thyroid "Euthyrox, this is an awful medicine. Firstly, I live in Europe, but in a country that is not in the EU, but in Southeast Balkans. Whatever, I was diagnosed with Hashimoto's thyroiditis in 2019 and was put on thyroid replacement drug, 25 mcg of levothyroxine, which in my country, N. Macedonia, you can only find under the brand Euthyrox by an American-German company, Merck. From the very first day, I had horrible side effects like skipping heartbeats, fainting, headaches, digestive problems, dizziness, sleepiness, blurry vision, brain fog, and general mood swings. I tried several times to stop this medicine, I felt great, but as the symptoms of Hashimoto's persisted, the doctors advised I keep taking. I got used to feeling like this, doctors raised my dosage with time from 25 mcg to 50 and then 75 mcg. Very often, when I take this pill in the morning, my libido, mood, and zest for life go from great to almost zero. I really hope I can find a source of supply of some other brand of levothyroxine to switch to."

• joy...
• Taken for 1 to 6 months
• September 9, 2021

For Underactive Thyroid "I have been on thyroid medications (Synthroid and levothyroxine) for quite a few years with no problems and good results/bloodwork. Several months ago, Walmart Pharmacy placed me on Euthyrox, and it has been a downward spiral since that time. I began experiencing many symptoms that only continued to worsen over time: muscle aches, fatigue, brain fog, headaches, dizziness, dry mouth, weakness. It was relatively easy to tell myself I was depressed, I was working too hard, it was age-related (I am 74), and on and on. Finally, I went back to when my symptoms began and knew the only change in that period of time was my medication. Then I checked out patient reviews of Euthyrox and knew I was not alone, so why is this medication still being prescribed? I called my pharmacy to put me back on my levothyroxine and never substitute that medication with any other drug again. My following lab level also showed a decrease in my level. Why is it still out there?"

• Eut...
• Taken for 1 to 6 months
• December 19, 2021

For Underactive Thyroid "On a whim trying to figure out what is wrong with me. No doctor seems to help me. I researched the difference between the two drugs & mercy. Have I found the culprit? I have been feeling so lethargic, insomnia, weak, dizzy, fast heart rate, sweats if I try to push myself and faint. Physically unstable, nauseated, ankle and leg cramps, foggy, foggy. Memory getting bad, vision, headaches, chest, indigestion. I was given Euthyrox by Walmart instead of Levothyroxine. Taking for 3 months. Changed pharmacy in the meantime to Walgreens. I picked up new 90 Levothyroxine."

• DCG...
• Taken for 1 to 6 months
• February 22, 2022

For Hypothyroidism, After Thyroid Removal "I do love the internet for this type of communication. Wal-Mart switched me back in late November 21 to Euthyrox. By late December, I thought I was going to need my prostate removed. Body aches, joint aches, fatigue, and brain fog to boot. Do not let it happen to you. Back on levothyroxine, and after 2 days, everything improved."

• Car...
• Taken for 1 to 6 months
• March 18, 2022

For Hypothyroidism, After Thyroid Removal "This stuff is awful. Had thyroid removed November 17th, 2022. It took a while to get my levels normal. When they finally were normal, I felt terrible. Chest pains, anxiety, going from cold to burning up, insomnia, loss of focus, and so much more. Through the grace of God, I found this website. The doctor immediately changed my medication when I showed him what I found. It is really bad and makes you feel out of control because you can't slow your heart down or do anything about the anxiety. I have been off of it for 3 days, and I am praying the side effects go away soon. If you are having these problems, take a deep breath and give yourself a break. Exercise was the only thing that would help, but the chest pain, fast heartbeat, and anxiety would come right back. Tell the people around you so they can give you a break. It makes everything really hard, and the smallest thing will frustrate you, and then you feel worse. Try to remember it's the medicine and not you, and it will get better."

• But...
• Taken for 1 to 6 months
• September 26, 2021

For Underactive Thyroid "The Euthyrox is horrible for me. Took it for a month, maybe more. Had headaches, terrible fatigue, muscle cramps, foggy brain. Probably more symptoms, just didn't make the connection. After researching, I read all the side effects. Went to Walmart and told them I did not want this Euthyrox anymore. It is confusing when I compared the generic of Synthroid and Euthyrox, it both said Levothyroxine. I told the pharmacist I no longer wanted the Euthyrox, but if they label it all as Levothyroxine... my rx history only shows Levothyroxine. So very leery. Will be asking for Synthroid generic to be more specific. See if that changes anything. Until then, I am miserable right now. I suggest DO NOT TAKE EUTHYROX."

• Car...
• Taken for 1 to 6 months
• July 22, 2022

For Hypothyroidism, After Thyroid Removal "This medication does not work the same as other thyroid medications. I have been on thyroid medication since I was 15. Walmart switched me to this one, and the pharmacist assured me it was exactly the same. I trusted them, and they were wrong. My levels shot up, I started gaining weight (40 lbs), I’m swelling, have brain fog, am irritable, heat and cold intolerant, and I’m so tired during the day but can’t sleep at night. I don’t understand how this can be given to us without them fully explaining the differences in the medications. This could be very dangerous for someone like me as I no longer have a thyroid. My doctor wrote me a new prescription yesterday, and when I got home from getting it filled, I realized they gave me Euthyrox again. I had to go back up to the pharmacy and have them switch it. They apologized for giving me the wrong one and replaced it because my doctor included in the notes to not give me Euthyrox anymore. I can’t wait to start feeling better again."

• Deb...
• Taken for less than 1 month
• June 5, 2022

For Hypothyroidism, After Thyroid Removal "Horrible medication. I’ve tried taking it several times, but kept having to stop after just a few days. I feel as if not taking anything. Horrendous fatigue, severe brain fog, I’m freezing cold, slow pulse, body aches, puffy, irritated eyes, etc. Look at the horrible reviews! Out of 130 people, it scored an average of 1.6, which is what you’d choose to indicate it’s ineffective, and 93% saying it’s terrible. How is the FDA not reviewing these complaints?"

• Eut...
• May 23, 2022

For Hashimoto's disease "I had it after taking generic levothyroxine from Walmart. This time I got the Euthyrox, and I have been experiencing brain fog, extreme pain in my feet since morning, and fatigue."