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Can GI Problems Interfere With Thyroid Medication?

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Q. I have suffered with stomach pain and reflux for a long time. I have tried Zantac and Pepcid without much success. I am now taking Prevacid that my doctor prescribed to control excess acid. Even after an increase in dose I am still experiencing gastrointestinal upset. Any ideas?

I also have a thyroid problem. My endocrinologist started me on Synthroid and recently switched me to Levoxyl. Now I am noticing side effects. It seems as if the drug isn’t working the way it used to. I know these drugs are supposed to be equivalent but my body says something different. Should I ask my doctor to put me back on Synthroid?

A. Substituting one brand of levothyroxine (Levoxyl) for another (Synthroid) may require an adjustment in dose. But first, you and your doctor need to consider your stomach problems.

An article in The New England Journal of Medicine (April 27, 2006) shows that people with low stomach acidity do not absorb levothyroxine well and may need a higher dose. The Prevacid you are taking reduces stomach acid.

People infected with stomach bacteria called Helicobacter pylori also seem to have trouble absorbing thyroid hormone. This bug may also be contributing to your GI problems. We discuss the treatment of this infection in our Guide to Digestive Disorders. Our Guide to Thyroid Hormones has more information on levothyroxine and other drugs that may interact with it.
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I took Prevacid for years due to severe reflux. Remembered my father took 1/4 - 1/2 teaspoon of baking soda twice a day and I tried this also. It worked after several days, so stopped taking Prevacid and have not taken since. Told my Dr., and he grinned and wanted to know how I knew to do this. Asked him why he never told me this since he knew this remedy! Also lost a few pounds which also helped. With a flare-up of reflux, I take some baking soda, which always works.

You have three major symptoms of celiac disease or gluten intolerance--acid reflux, stomach pain, and thyroid problems. Doctors rarely check for this genetically common intolerance. Do yourself a favor and go to and get yourself checked for stool antibodies to gluten. Your doctor can test for antibodies in your blood, but the antibodies can be detected earlier in stool samples.

There is quite a bit of negative info recently about acid reducers. Another old time remedy is apple cider vinegar (about one tablespoon a day). I suggest organic unfiltered. There are many ways to take it such as mixed with honey in warm water or stirred into pineapple juice, etc.

Forgot to add in the baking soda remedy to mix this in a glass of water and then drink.

I'd been on the same dose of levoxyl for 10 years and levels were fine. After taking Prilosec for a year, the levels began changing and found I had to change the levoxyl dose. My Dr. said not to take them together or the Prilosec would absorb the thyroid med. I now take levoxyl in am (as directed) and wait an hour or so and then take the acid reducer. Seems OK now.

I take Synthroid early morning and take the Prilosec about 3-4 hrs later. I haven't noticed any issues with it. My biggest issue is trying to lose the 30 pounds I gained in two years before I found out I had a thyroid problem.

I have been taking both levoxyl and prevacid for the past 5 1/2 years since I had my thyroid removed because it was 3 times larger than normal but not diseased. I have found that for both medications to be effective, I take my levoxyl in the morning and my prevacid in the evening.

i also take throyid and nexium together and have had a lot o problems.Going to try spliting them up and see what happens.

I have been taking Synthroid for over a decade and was just recently diagnosed with IBS and stomach acid issues. I was told to take Prilosec in the morning before my first meal. This is also when I take my Synthroid, so I didn't think anything of taking them together. After one week I felt so tired I could barely get out of bed, realized the Prilosec must be interfering with the Synthroid's ability to work, and am now switching to Synthroid first thing in the a.m., Prilosec with second meal (luch) of the day. Hopefully this will work (and I hope it helps).

I have many issues with my health, and recently I've been picking up more information on Prilosec and how it may be affecting my health. I have optic neuropathy, I've lost my peripheral vision. I also have Pernicious Anemia which is a lack of B12. Did you know you could go blind with Anemia? Me neither, but you can.

Also, I have chronic gastritis and Graves Disease which is thyroid disease. I also have Graves Eye Disease, where my eyes bulge out of my head, they are extremely dry and my eye lids barely cover my eyes. I have taken Prilosec for about ten years, prescribed by various drs. for chronic stomach pain and GERD. I've had three endoscopies.

Why didn't they just fix the sphincter where my stomach meets my esphophagus? Because Prilosec suppresses the acid in the stomach, it also messes with the flora and fauna that should be working. It has left me with no Intrinsic Factor, hence I cannot absorb B12. I have to give myself shots of B12 bi-weekly. Recently I came upon an article about Prilosec causing thyroid disease, which I also have.

To sum this up, I think Prilosec made me go blind from lack of B12 and also has destroyed my thyroid, I take 200 mcgs of Levothyroxin everyday which is a very high dose. I've been told my vision will not get better. I have lost my driver license. Where do I go from here?

I am taking Synthroid and have just been prescribed Avapro for High Blood Pressure, Crestor for High Cholesterol and also CoQ10 vitamin for high blood pressure and Selenium for my thyroid condition (these two last pills are vitamins/minerals. I am now experiencing terrible heartburn and I am not sure what pill(s) are doing this. I do not want to take any more meds (for heartburn) I was told by a friend to take 1/2 tsp. baking soda. If I did this, when would I take it as not interfere with my thyroid pill? I take the synthroid in the morning.
Please, I am suffering with this heartburn and cannot get answers from my doctor.

I too was taking all the meds and vitamins you described.
I also take Prevacid for Acid Reflux. Did not know what pill was giving me so much heartburn. Researched, researched, went off Crestor first, heartburn disappeared, went off vitamins, until my heartburn really clears up.

Currently taking Avapro for high blood pressure, Prevacid, Synthroid and Omega 3 for hair loss and nails. Doctor now wants me on Vitamin D, because I'm so cold all the time. My daily regime:-
As soon as I wake up, anytime, I take my Synthroid, wait at least 3 hrs, take my Prevacid, wait about an hour then take my high fibre drink and then my Omega 3. I take my Avapro at dinner time. My research revealed that a high fibre drink can interfere with the thyroid absorption, that is why I wait at least 3 hrs.

The Avapro when I took in the morning, made me extremely fatigued, again researched, this is one of the side-effects, even tho doctor disagrees, I read it on different web sites. After taking it at supper the fatigue has disappeared. My suggestion anytime you have doubts what to mix with your thyroid med., go to goggle type in (example: thyroid pill and prevacid) and you will get more than enough info. Doctor's do not know how YOUR body works, they are going on general data. Hope this helps

I have been taking Synthroid for 30 years after having a thyroidectomy due to Graves disease. Recently I went to a naturopath for the first time regarding some digestive and hormonal issues. The slippery elm powder and probiotics she recommended have worked better than any antacid medication I've ever taken.

In addition, I've learned that raw cruciferous vegetables and non-fermented soy products should be avoided by people with thyroid problems as they are goitrogens. Glad I found this out as I'd been increasing my soy intake to combat perimenopausal symptoms.

I've been taking Levathroid now for 15 years after partial removal of my thyroid. I just recently learned I've been taking it at the wrong time. I was taking it along with breakfast & all my other meds. & vitamins (Prevacid, Hydro. Lopressor, Klonopin, Estrace, multi vit., Acedophilus, Citrucil & fish oil) Now I learned I should take the Levathroid 1st thing in the AM 4 hours before the Previcid & maybe other meds. They also told me to take the Previcid 1st thing in the morning!!!!! Help!!! I'm totally confused!!! Also I can't wait 4 hours before I eat breakfast & the Prevacid is to be taken before I eat. Can anyone help me coordinate my med schedule!!?? Thank you

I can certainly relate. I gained 80 lbs before they determined that was my problem. Haven't been able to take it off in 8 years. Now I have celiac on top of that.

Try taking your thyroid medication at night 3 hours after your last meal and see if it helps, but I would consult your doctor first ... I did this and it helped a great deal. I am on levoxyl ... that way the levoxyl will be diluted in your system and not interfere with other meds. Hope this helps ...

I have had acid reflux/GERD for a couple of years. I had tried everything, ie Previcid, zegerid, protonix, nexium. Nothing helped and it became very expensive. Finally I purchased Ginger Root from a whole foods store and finally relief.

Every doctor I go to has different opinion, but nobody knows what is right. I take Synthroid, and take Nexium and some natural supplements (like Omega 3....) and I am so tired I could not get off the bed today. I am very upset. Nobody knows how to help.

I love this! I use it when I have heartburn and it REALLY works! Taste bad but works great! My mom taught me this years ago. Thanks for sharing!

I take levoxyl and was prescribed nexium for acid reflux. Directions are to take levoxyl 1/2 to 1 hour before eating and on an empty stomach and nexium 1 hr before the first meal. Obviously I cannot do both unless I don't eat until after 11 AM every day as they are supposed to be taken at least 4 hours apart. If I take levoxyl before bedtime will it keep me up at night? What do others do when you have both issues?


I've gone thru holy heck with my thyroid and have advice for ALL you thyroid sufferers out there (and how to take your meds). I was diagnosed with a completely non-functioning thyroid at 29 (along with Hashimoto's) and put on a full thyroid hormone replacement .1 of Eltroxin (brand name). It didn't work very well, so after a few weeks I heard that Synthroid was the Cadillac of thyroid meds because of the quality control and consistency of dosage and I asked my doctor to switch me. I've been on it ever since and I'm 46.

Everything I've read is that YOU SHOULD NOT SWITCH BRANDS ONCE YOU'RE ON ONE BRAND FOR A LONG TIME. Doctors should know that. But they tell you they're all the same. They tell you you can take your thyroid meds at bedtime or morning. Wrong. Take it first thing in the morning with water, and then EAT AND DRINK NOTHING FOR ONE HOUR. One complete hour. No OJ, no coffee, no nothing. If you want to, you can set your alarm for one hour before you get up, pop your pill and go back to sleep. I suffered for 15 yrs with my thyroid medicine not being fully absorbed because I took my Synthroid at night or in the morning and didn't wait a full hour. I was tired all the time, had all the other awful hypo symptoms.

As far as other meds and vitamins go, I believe they will interfere. Take them at night. Separate them as far apart as you can from your thyroid meds. If your underlying, pre-existing, major health problem is thyroid, TAKE CARE OF THAT FIRST. Preserve what's working for you with that.

I JUST got diagnosed with gastritis and esophagitus and am in my third day taking Prilosec. (These 2 diseases may be the result of hypothyroidism/Hashimoto's. They are auto-immune diseases like thyroid. The doctor couldn't tell me exactly what caused it. He said it could also be stress or menopause. I may be on Prilosec for a long time.) I was told to take my Prilosec pill in the morning (after waiting an hour after taking my Synthroid) but after reading y'alls comments, I'm switching to the evening. The Prilosec is working well, but I might try the baking soda also! Thanks guys! I think it's really important to "layer" meds, and remember which disease you got first and take care of first things first...

Well, it's clear from comments that thyroid is still far from understood by most internists/md/s. When I asked my doctor for an endo referral she said, "you don't need that." I was recently switched by new insurance (thanks, not) from Synthroid to Levoxyl, from Avapro to Diovan.

I also have constant heartburn so doc said take Prevacid indefinitely even though labeling says 14 days at 4 month intervals. H'Wha? Prevacid and Levoxyl are to be taken first thing in the morning on an empty stomach. OK which one first? Then I learn and you all have reiterated that antacids interfere with thyroid hormone absorption. All extremely frustrating and bamboozling. Unbelievable really.


I have been reading all these comments. I can relate to some of them. Does anyone out there with thyroid issues have symptoms that relate to the sinuses such as what appears to be a sinus infection (pain in sinuses, green/yellow discharge, ear pain, ear canal pain, etc...)? My symptoms are localized to the sinuses and I'm having a hard time finding information on it. Have been struggling for 6 years now and have seen more than a dozen doctors.

I am on my way to Mayo clinic in August. The odd thing is that acid reducers help my sinus problems. I do not have acid reflux (did the Bravo test a month ago) but taking an acid reducer helps my sinus problems. Any thoughts?

Glad I read all this, as I was going to take Prilosec due to a flare up with reflux. A number of thoughts:

1) highly recommend the book "The Thyroid Solution" by Ridha Arem M.D., Clinical Professor of Medicine @ BaylorCollege of Medicine in Houston Texas. Dr. Arem is an endocrinologist with a specialty in thyroid issues. I fought w/my doctors for years over thyroid symptoms with "normal" labs, all on the low side. Had I had Dr. Arem's book to refer to, I could have saved myself a lot of time, suffering, and research. My sister's friend, who lives in Houston, was not getting better on Synthroid. She consulted Dr. Arem without knowing about his book. He changed her dosage and added T3, and she got better. She loves this doctor.The book is commonly available. ( Barnes & Noble, Amazon etc.)

2) A lot of you sound like you are being under-medicated w/ thyroid meds. Your doctors should be testing your free T4 and free T3 levels in addition to TSH. Many people require T3 in addition to T4. I am one of them. I didn't start to get better until I insisted my doctor add T3. Three days later, the grinding depression lifted for the first time in 10 years, I could think clearly and focus my eyes.Three weeks later I had lost 15 lbs. of myxedemic weight without exercise or diet change. Muscle aches and gastrointestinal problems also resolved.THIS WILL NOT BE THE CASE WITH EVERYONE. The free tests will show if you are deficient. They should be in the high side of the range. TSH is NOT a thyroid hormone. It is produced by the pituitary gland. It should NOT be the only lab they rely on for diagnosis.

3)The FDA allows generic medications to have a variable fluctuation of 10% active ingredient. This is impossible for thyroid patients, who must be stable on their meds. and is a source of controversy in the medical community The generics also differ from manufacturer to manufacturer, whereas Synthroid is the same all the time. This is why many doctors insist on Synthroid. That said, some people don't do well on Synthroid and have side effects such as hair loss. For whatever reason, these folks do better on the generic. If for any reason you must take the generic ( managed care,etc.) you MUST make sure that your pharmacist gives you the meds. from the SAME manufacturer each time. Mylan Labs is the manufacturer who made the original generic when Synthroid came out of patent. Mylan sets the standard for generic T4, and therefore their drug is tested by the FDA every 4 months to make sure it is identical in strength to Synthroid. They also keep an archive of each batch, in case they need to be tested for any reason. I have my doctor request Mylan Labs as my generic on the prescription. Pharmacies must honor this request, and I still pay a generic price.

4) After doing well on my meds for about a year and a half, I experienced an episode of thyroiditis. I had to cut the dose of T3. Within 5 days I was clinically depressed, and had blurry vision and attention deficit. Within 3 weeks I gained 15 lbs. However the symptoms of hyperthyroid went away in the same 5 days. After a month my meds were increased, the depression etc. went away, but the 15 lbs. have stayed. It's been about 7 months. This is not to complain, but to show what a tricky business this thyroid stuff is. Perseverance furthers. After all, what's the option?

5) Gastrointestinal problems are definitely associated with thyroid and I'm dismayed mine have returned. I hate looking 6 months pregnant because of the bloating, hate that burning feeling in chest and throat, hate sleeping sitting up. Weight gain around the waist is dangerous to the health. The fact that it is all over other parts of my body too and looks like cellulite lets me know it's from myxedema, which is from my thyroid problem. I'll have to keep trying to get my meds right. But I'm glad to remember about the baking soda. My grandparents always did this, and my Mom gave it to us when we had upset stomachs as children. It always worked ! How often we forget the simplest things, right ? Keep on trucking, all you folks out there in Thyroid-Land. Hope this helps you.

My gastrointerologist prescribed omeprazole for my sinuses. He informed me that the acid reflux is causing distress to my sinus cavity. He was right. Taking the reflux meds totally eliminated any sinus problems. If I don't take omeprazole, my throat has mucus caked on it every morning, sinus drains, nose stuffy, ear pain and face pain. It works.

Reading your post, and it made me think... Got diagnosed with thyroid issues and just starting taking levoxyl for it. The reason they found my thyroid problem was when my Dr sent me for a CT due to an inner ear problem. This is the 4th yr in a row that when fall rolls around I get fluid in my left ear, then an ear ache, then it turns into a equilibrium problem. The only solution for me is to finally get a script for prednisone. The ENT still can not figure out why I get this or why my ear tingles all the time. Wonder if this is all tied in....

Saw your post b/c I am having problems with taking my levoxyl first thing and trying to figure out when to take my prilosec for terrible heartburn. Seems like many people with thyroid problems have heartburn issues as well. Started taking the prilosec in the evening instead of morning and it isn't taking the heartburn away like it used to. SO FRUSTRATED!!!

I started taking levothyroxine 2 months ago and after about a week developed severe reflux. She measured my thyroid levels after 30 days and they were not much improved. She recommended I get off the levothyroxine for 2 weeks to see if it was causing reflux. That night the reflux went away completely.

Two weeks later I started Synthroid. The same day I experienced the same reflux I had on levothyroxine. I am convinced that this medication can cause reflux in some. I am frustrated because my doctor says it isn't possible. Now I need to correct my hypothyroidism but can't take thyroid meds. Should I try t3 medications? Otherwise I have never had reflux.



I was diagnosed with excess acid in my stomach a couple months ago. I was also having severe sinus problems. My doctor told me that my sinus problems would at least partially clear up when the excess acid in my stomach was reduced. The acid reflux can inflame the sinuses, causing extra postnasal drip and congestion.

After reading all of the feedback about the acid reducers, I think I am going to try one of the natural remedies. Does anyone know if the baking soda or apple cider vinegar is more effective?

I have used the apple cider/honey remedy (1 tsp. each in water) after going off prilosec. Found it very helpful. It doesn't make sense and the doctor laughs, but it works.

I didn't realize until I read all these postings that reflux is related to thyroid problems/meds. Interesting. Haven't heard of the baking soda remedy - whats the "recipe"?

Hi, I tried all the T4 and had terrible heartburn. I stopped the T4 and heartburn stopped. It does cause heartburn in some people. My reflux problems stopped when I went off the meds. I cannot take any of the T4 meds. I am on Armour. Thanks to all and I hope this helps.

Hi would luv to talk to you more about thyroid and nexium for acid reflux after the holidays?

I was told also to take both in morning and I am also concerned about my thyroid first and want to continue to take in the mornings, and take the nexium at bed time or evening time (couple hrs before dinner)? This is all confusing, I just want to be healthy and spend time with my beautiful daughters. :)

Any help and guidance is appreciated. :)

I've been on thyroid replacement for 25 years and have never been "right" on the dosage doctors insist is correct, according to blood tests. When they reduce dosage from effective level I get sinus infections and other immune system related ailments such as Shingles.

I get really tired of hassling with doctors who know it all. I also am sporting a real issue with reflux but Omeprazole seems to help. I have never, in 25 years, been told not to take antacids with the thyroid replacement or that there is a causal relationship with thyroid meds and reflux. Live and learn but don't let your doctor run your life.

Well I can lend some insight to all this...I have hypothyroid and reflux. I never had any reflux or heartburn problems until I was diagnosed with my thyroid problem. Now, I have been to many Doctor's and specialists as I make full use of our free medical. Anybody with a thyroid problem MUST keep at their Doctors or change your Doctor if they don't listen to you.... don't take your doctors word on the dosage until you feel good.

My first Doctor said that when tested I was within the "range" so I should be fine. Ummmmm wrong! I still didn't feel at the top of my game so I went back and insisted they up the dosage... waited six weeks, retested and my doctor says... you're good cause your still within the "range".. well let me tell you, the "range" is big. I told my doctor that I still didn't feel totally up to par and that I wanted to increase my dosage again. I argued with him but ultimately won as this is my body and I know best.

Well in six weeks I was feeling great, was retested and I was still in the "range" but on the higher end of the range and that is where I finally settled as I felt good there. See, so we must keep at our Doctor's and insist upon what we need as each individual is different and our needs of dosage are different. I do agree after experience that your thyroid med should be taken first thing when u get up on an empty stomach and no food until an hour after. I also believe that thyroid and reflux come hand in hand and each person will just have to find what works for them..i.e. baking soda, prevacid or the many other alternatives out there.

I take levothyroxine for thyroid and my reflux I use baking soda as I would rather go more natural than more of the man made drugs that have side effects. Also, EVERYONE that has a thyroid problem should have their free T3 and T4 tested with TSH cause in some cases thyroid patients need T3 and maybe this is you ..the person out there who still doesn't feel well on the medication. Your never going to feel a 100% anymore as we do have a disease and our bodies are not functioning like someone without a thyroid problem but I am here to say... we can feel pretty dam close.

200 synthroid, hashamito thyroidist, possible liver disease, acid in stomach, watermelon stomach, arthirtist, fifibro, eye problems, horrible dry skin, sinus problems, bones removed from moth, tmj, gum disease, fast heaet, trouble breathing, sleep apnea, oxygen at night and I am 55, this all started 5 years ago and this all his horrible. I am so tired all the time. I would rather be working than sick like this every day. Everything seems to be attacking me. Not the life I planned for.

What is the recipe for the baking soda remedy? Have Hashimotos and am on Synthroid .75. Synthroid seems to be working pretty well but I have started having reflux issues. Would like to try the baking soda remedy since taking Prilosec is complicated since you're supposed to be taking both on an empty stomach. Please let me know.

Baking soda recipe: 1/2 tsp baking soda in 4 oz. water. Can be taken every 2 hrs. no more than 7 doses per day. The recipe is on the [Arm & Hammer] box.

I'm currently taking synthroid and my levels have remained consistent even thru two pregnancies! I started out eight yrs ago with levothyroxine but I had headaches with it, so I switched to synthroid. It's more expensive but well worth it! My advice, find what works and take it faithfully! It is painful to try to function in daily life when you feel like a zombie and cannot keep a clear mind! I don't suffer from reflux ir heartburn as I see many here do, but I have a lactose intolerance and what works for me is honey and cinnamon before or after every meal you know will affect you. No certain mix, I just mix about a Tbsp of honey to a few shakes of cinnamon.

What vitamins were you on that they gave you reflux? If Avapro is for Hypertension, have you tried supplementing with potassium rich foods? That would be fruits and veggies, even rice bran. Kelp meal which is loaded with all the microminerals. On magnesium? Mag and zinc are needed for over 300 cellular processes.

Look uo the youtube version of Dead Doctors Don't Lie by Joel Wallach. He's a vet and advocates for people also to get their minerals.

Also look up soilminerals dot com, and see how deficient in minerals most foods are anymore. I have a small farm and have found to replace antibiotics with vitamins and minerals in a freechoice form for my animals. So they take waht they need and heal themselves or stop it before it gets started. Mastitis for example is magnesium deficiency. Magnesium is a natural anti inflammatory. Vitamin C is also an antiinflammatory.

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