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25 mcg Synthroid ... Bad Reaction??
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25 mcg Synthroid ... Bad Reaction??

I was recently diagnosed as being hypothyroid.  I was prescribed 25 mcg Synthroid as a starting dose, which I understand is a very low dose.  I take no other prescription medications.  I only take a daily multi vitamin/mineral (for many years).  Everything was going fine until I had been taking it for ~4 weeks.  At the 4 week point, I started with having difficulty falling asleep.  Everytime I would start to drift off to sleep, I would get a "jolt" of energy and I would be wide awake again.  As each day passed, things got worse.  I became so anxious and jittery that I was only able to get ~3 hours of broken/restless sleep a night.  Basically it was like having a 24/7 panic attack.  I suspected it was the Synthroid since I knew it took a few weeks to kick in so the timing made sense.  I am wondering if 25 mcg of Synthroid was too much for me and has caused me to go hyper?  Seems odd for such a low dose.  I took the Synthroid on Saturday, but haven't taken it since because I was feeling so terrible.  My doc isn't in until Tuesday and I plan on calling him then, but I didn't want to keep taking something that was causing such a bad reaction.  I have skipped two doses of Synthroid (Sunday and today) and I know it takes awhile for Synthroid to leave your system, consequently I am still feeling anxious/jittery/insomnia, almost like I drank several cups of coffee (I don't drink coffee and stay away from caffeine).

Has anyone else experienced a reaction similar to mine on a very low dose of Synthroid?  If so, what was the outcome?  Any advice would be greatly appreciated.
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It sounds like you are experiencing some hyper symptoms.

Some of us are very sensitive to thyroid meds and have to start off at a very low dose and increase at a snail's pace.  My last increase was 6.5 mcg, but it drove me right over the edge to hyper. My endo told me not to take anything for three days and then resume my former dose.  If you're 1) over 50, OR 2) have been hypo for a long time, or 3) have a history of cardiac arrythmia, 12.5 to 25 mcg is the recommended starting dose.

Do you know what the actual numbers were for your free T3, free T4 (and FT3 and FT4 reference ranges) and TSH before starting Synthroid?  The two possibilities here are that 25 mcg was too high for an initial dose, or that it's too high for you period.

Were you having hypo symptoms before starting on Synthroid?

Some people also find that switching brand names alleviates some of the side-effects.  Fillers seem to be the culprit there.

Goolara has made some valid points but a long time ago, I discovered that the jittery, anxious feeling you get when Hyper, can also be from hypo too.
Most think that the fast heartrate and the anxiety (panic attack type stuff) is from hyper when in actual fact, I have felt them both ends of the scale....both hyper and hypo.
The only difference being that when Hypo I ache like Hell and when Hyper, I could clean the house in 1/2 hr flat.
If it is the Synthroid, you would start to feel better by the 2nd day of the missed dose.
See yr Doc and see what he/she says.
Goolarra, I am 30 years old and have suspected that I am hypothryoid for a long time (since finishing college).  My great-grandma, grandma, and mom are all hypothyroid as well.  Previous bloodwork 2 years ago resulted in everything being in normal ranges according to the doctor but he didn't quote any numbers at that time and I was shy about asking.  Things started getting bad in September of 2008 and kept getting worse.  I had pretty much every symptom of hypothyroidism with the exception of the fingernails being dry and brittle.  In Dec/Jan I started noticing alot more hair in my hairbrush and in the shower drain.  I told myself it must be the new brand of shampoo and conditioner I was using.  I started my period in mid-January (after having skipped a few in late 2008) and was still bleeding in mid-April.  That's 12 weeks of constant non-stop bleeding!!  I kept putting off going to the doctor, because I told myself it would stop anyday now.  Finally in mid-April, I became so weak and fatigued and could no longer deal with the bleeding, so I went to both my PCP and OB-GYN.

My PCP did a bunch of bloodwork and called me a few days later and said, "Hey, how are you doing?  No wait, don't answer that.  I can tell you how you are feeling based on the bloodwork ..... You feel like ****!"  He went on to tell me that the bloodwork showed I was hypothyroid.  He said my free T4 was low.  He quoted the value and acceptable range, but I cannot remember it exactly.  I just know it was below the acceptable range.  I know he tested the TSH, but he didn't mention it and I failed to ask because the conversation quickly transitioned into treatment with Synthroid.  25 mcg Synthroid to start and I was to come back in 6 weeks for follow-up bloodwork.

The first 2 weeks on Synthroid I felt nothing, good or bad.  The 3rd week I started feeling more mentally "clear" and could focus and concentrate better and felt a little more energy.  I was thinking, hey ... this stuff is really helping.  When I reached the 4 week point, that is when all the problems started as described above.  I last took it on Saturday, which would have been 5 weeks and 1 day on Synthroid.

Since skipping Sunday, Monday, and Tuesday I am feeling better.  I actually slept last night for 9 hrs (much needed).  So I definitely think it is the Synthroid pushing me hyper.  It still seems odd for such a small dose, but perhaps I am just super sensitive to it.  Unfortunately I didn't get a chance to call the doc today.  While I don't want to take it and feel like ****, I was definitely seeing some benefits at 3 weeks.  At this point I am torn about whether to keep taking it.  Perhaps 12.5 mcg will do much better for me.
I am definitely in the "extremely sensitive" category, too.  It may be that you could eventually end up taking 25 mcg (or even more), but that you just have to start very low and increase very slowly. You have to give your body a chance to adjust to the "new" hormone.  

I also feel that I was probably slightly hypo for a very long I came out of the womb that way!  And, suffice it to say, that's over 50 years ago.  Since I've been on levo for the past year and a half, I feel in some ways better than I felt all my life.  For instance, I've maintained my weight since being on levo...never before could I do that for even a month.

I fit all three of the categories above for starting out on a low dose.  My PCP started me at 88 mcg....yikes!  That lasted about two weeks, and I started having side effects.  PCP lowered the dose to 44 mcg.  Two weeks later and down to 25mcg and I still had side effects.  I know the 25 still bothered me...don't know how much the residual 88 and 44 affected that.  Then I got on something to counter the levo side effects(I was starting to go slightly crazy) and started building very, very slowly - it took me a year to get to my current dose of 75 mcg.  I'm still not ready for 88!!!

Talk to your doctor, and see how he feels about cutting you back to 12.5.  After five weeks, you can repeat the bloodwork, see how you're feeling, and try a slight increase then if you and your labwork feel you need it.  Don't wait too long to get back on meds.  You don't want to start feeling hypo again.  Slow and steady will get you there.
That's what happened to me also when I was taking synthroid.  That's when they found out I had Hashi's that a possibility?
Yes, I have Hashi's too, and I'm sure that contributes.  Our thyroids periodically decide they want to work for a minute or, worse yet, "dump" some extra hormones.  However, I think there's also something to just being extraordinarily sensitive to thyroid meds  Smilerdeb doesn't have Hashi's, and she's unbelievably sensitive, also.  I feel like my thyroid has most likely always functioned at a pretty low level, and all this replacement hormone has shocked my body like crazy.

Banana27 could definitely have antibody tests (TPOab and TGab) to see what's going on with an autoimmune condition.  Good suggestion.
True Goolarra....I have Graves Disease and although I had RAI and TT, I am still super sensitive to meds (any kind of meds).
I cannot tolerate Codein, Morphone or Pethidine....the only surgical pain relief I can tolerate is Tramadol.
I cannot take any penicillin, and there is only one anti-biotic left now that I can take so I dont take them unless I am dying literally.
I get anaphalctic shock from most meds now.
So I lean more to natural therapies for colds, coughs, flu etc.

Eutroxig (sodium Thyroxin) is the same ....I started at 25mcg, went to 50mcg, went to 75mcg then BANG! went hyper.
So I had to start from scratch all over again increasing my dosage by 1/4 tab (12.5mcg) weekly.
I am now on 62.5mcg 7 days a week and my Doc doubts whether I will ever get up to 75mcg again.
Some people are just super sesitive....and thats when baby steps should be taken with doses.
Each fortnight if labs show an increase needed ...only increase dosage by 12.5mcg weekly until you get the levels right.
Baby Steps lol.
After my initial start at 88 and backing back down to 25, I took those baby steps, too.  25 to 37.5 to 44 to 50 to 62.5 to 68.5 to 75 to 81.5 (and that took me a year!).  And I hit the wall at 81.5 and I'm now back to 75.  I have my doubts about ever getting to my original "starting" dose of 88, too.    

Yeah Goolarra......I have doubts on hitting 75mcg.
It just goes to show that everyone is different depending on symptoms.
Feeling great at the moment...lady of leisure for 3 weeks lol :)
I started taking half this morning (12.5 mcg).  Wish me luck.
listen i went yrs so tired gained 100 pounds or more unknowinlgy i found out my thyr was barely functioning. it took 3 months to get my levels correct and i did start loosing weight without trying. but it is IMPORTANT to not miss your endo appts. I did and became real sick. So alwasy keep your endo appts and communicate with your dr. If he rushes you out the door say I am not finished. He will sit back down and let you finish. It maybe about money for them it is about your life with you. Fight for your life. I did and it paid off. Synthroid has worked great for me plus i have a GREAT endo dr in houston texas. He took me up small increments. He spceializes in thyroid and ddiabetes. His name is dr Orzack onM ain Street. At .125 I lost 10 pounds without trying.
Yeah I too have lost 10kgs (22lbs)  of the weight I gained (17kgs) before RAI but only as my levels stabilised.
I havent been on a diet...the treadmill also has cobwebs on it lol.
I suspect you need some T3. You may ONLY need a T3 replacement.  You don't mention what your Free T3 was. This can show us that if it is low, that the T4 replacement you are taking is pretty much 'backing up'  and causing you hyper symptoms.
I suspect the doctor was trying to raise the Free T4 by giving you Synthroid.  This usually works for most people. Some people have trouble converting the T4 into Free T3.
The fact you were having hair loss and heavy periods, shows me that your body is not needing a T4 but  a T3 replacement. It would be worthwhile getting your Free T3's checked, if they haven't been done already. Also you are entitled to ask for your results. I would ask your doctor to give you  a T3 replacement for a short evaluation time.  Discuss this with your doctor.
Sounds like hyper to me, too.  Been there and I know that awful feeling of jitters and/or the fall asleep and then wide awake!
For thyroid problems that is not so severe you can try to do Pranayam (Breathing Exercise) everyday. You can find the demonstration in youtube.

"Yes, I have Hashi's too, and I'm sure that contributes.  Our thyroids periodically decide they want to work for a minute or, worse yet, "dump" some extra hormones".  

I'm new and trying to understand..more.

My daughter has Hashi's, she has been on 60 mg of the R. Armour since 2008.
She has an appt. with yet another new endo the 5th of Aug. Here are her recent lab's.

FT4  1.08         0.82 - 1.77    
FT3  4.0           2.0   - 4.4
TPOab   296     0 - 34

With her TPOab high...Is the "dump" of hormone's the same?

I've seen her switch back and forth between hypo & hyper several times...once...being admitted to a mental health facility. For...what I know now...was hypo symptoms. :(
(I'm thinking big time "thyroid storm").  
This was before treatment for her thyroid.

This attack wasn't as severe.


She went from extrememly hyper. Heart racing, anxious, jittery, not sleeping...etc.
Her GP had ran blood test's...he placed her on a low dose beta blocker plus, a sleeping pill.
Week's prior she was treated for sinus infection.

My question...will having an ab attack...

Will ab levels...level off over time, on it's own?

Her FT3 is in the higher range....would that require a dosage drop?

HDL Cholesterol            26     >39
LDL Cholesterol Calc    110    0 - 99

Vit D    19.2    32.0 100.0    (Upped the Vit, D supplement to 5000 IU daily)

Her prior thyroid doctor...told her to watch her diet and exercise. Otherwise...she would have heart disease.
She has a 3 year old and on the run constantly. Diet wasn't the issue either. Grrr.
(Doctor had a book)...roll eye's. book.

I'm concerned about heart issue's for a 25 year old.
Although...I do know that diet and exercise are most important.
Her number's started going off...and the man freaked.

I just don't know what to think...

Even thought... the filler in the new R. an issue.
Hoping for a rx for ERFA from the new endo.

Just looking for advice/thought's.

i was just perscribed for the first time. Synthroid 25mcg by my ENT....when i asked him what to watch out for as bad signs or ill effects of the medication he basically named all the symptoms you just described as having...heart palpitations, anxiety, trouble sleeping, sweating more easily, etc...he told me if i have any of these symptoms to come back immediately and see .  I would for sure contact your Dr.f and tell him you are having a reaction to the meds...good luck
I am so glad to find this sight as I thought I was loosing my mind. Now I find I am not the only one who has symptoms and has to work at trying to figure out how to take Synthroid in the right amount.  I started out on a generic and got so hyper and so irritated. I was definitely not my self. I felt like I was having a panic attack.  I asked my doctor to prescribe Synthroid. She was not happy about this.  I was going to take a break from the medicine and
wait but in a few days off the generic I was shaking again and felt like I had
to do something.  So started on Low Synthroid. 12.5 mcg.  I still think it might be too much for me. Now I have been on it for almost a month and have heart palpitations.  I think I better cut back.  I am not sure what the symptoms mean.  Am I taking too much or too little?  I was diagnosed with TSH 6.3 which is not so high.  I had no idea until the blood test that anything was wrong.  I was a bit tired and lacked motivation but i was used to it and didn't realize it was physical.
This is a very old, long thread, and you'll get much more attention to your individual concerns if you post your own, new thread.  Just go to the top of the page and click on the orange "Post a Question" button.

When you do, please post any recent labs you have.  Include reference ("normal") ranges as they vary lab to lab and have to come from your own lab report.

Heart palps can be a symptom of both hypo and hyper, so it's hard to tell which is causing them.  Tell us also if you've gotten any other new symptoms since starting meds.

I'll talk to you on the new thread...
Had you been using any iodine suppliments before your lab tests?  I had been cold for about a year. I started using Lugols iodine drops, the 2%. 2 drop a a day. My symptoms went through the roof. I tested and TSH 6.68. I had never bed hypoT to my knowledge before. My doctor started me on 50mcg. Long story short. I kept reducing because the iodine was creating false TSH number. I had nervousness, insomnia and heart palps with the meds. I think I may have Hashi's. My thyroid kicks in sometimes and produces and makes me hyper. But with a false TSH originally I was on WAY to high a dose.

I just finished 3 different strengths of Armour and had TERRIBLE cutting chest pains. I'm off that and will go back to Levothyroxine, very low dose.

Watch taking iodine even in suppliments. It WILL effect your numbers if you gave Hashi's for sure.
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