Side Effect - levothyroxine has it been known to cause severe anxiety attacks?

Yes, I have the same problem. My endo says it is something else because my blood work is fine.

I started taking 50mcg 4 days ago and Im very anxious already. I feel like im stressed out but im not. No panic attack yet but i can see how if this feeling of anxiousness continues it could lead to one. Also, from the 2nd day on, i have woken up several times before the alarm and feeling tired now. I actually felt good before i took the drug. All my numbers are completely normal. My tsh is 1.25 and all other tests are in the normal range too. The only reason i thought to see an endocrinologist is because im having fertility issues so he suggested i go on low dose synthroid just in case that might be the cause. Anyway, im not anxious about anything. Yes, its the drug.

Maybe you should re-examine the dosage. You said you take 50mg which is equal to 500mcg (mcg is the usual measurement for this med.). I take 75mcg, which equivalent to only .075mg. I hope it was just a typo on your end, and you're not actually taking that huge of a dose. You could give your pharmacist a quick call if it's hard to get a hold of your dr. Best of luck, hope this helps.

After being diagnosed with hypothyroidism I was prescribed this and looked forward to finally having a normal energy level. Starting dose was 50 mg. and I noticed the longer I took it the WORSE I felt. After maybe 5-6 weeks the anxiety started and got so severe Xanax barely phased it. Then severe mood swings with horrific depression and anxiety and I stopped taking it because as you know most doctors do not return phone calls (mine doesn't). 24 hours later I felt completely normal and have been since. I was warned if you don't see a specialist in thyroid disorders it could get ugly. Learned the hard way. I was never told this could even be a side effect either but it definitely can be.

YES! I was on a 25 mg dose for 10 days and I had a SEVERE panic attacks. Not only did it cause one, I have been on Klonopins for two weeks now after stopping the meds!!! Get to an endocrinologist who knows what they are doing!

Hello Mazza. No anxiety from this med for me. However, anxiety from my overall disease condition has happened. Hard to know the difference when a big change happens in our life.

Until your TSH is at a proper level of .5 to 3.0 and you are back to feeling normal, you may well continue having the effects from your original thyroid condition. .05mcg is quite low, so it may not be enough to counteract your condition. Many start at 88 or even 112mcg. Be sure you are being treated by an endocrinologist for your condition. They have the expertise and can help you evaluate and understand this treatment. A regular physician may not have the latest info for treatment and may be old school, so to speak. Your endocrinologist will be with you treating the thyroid condition for life, so good idea to find someone you can relate with.

The Endo will understand your anxiety and can help you. Especially during the six weeks or so for a full effect of this medication. any change in dosing is a very slow process. Hope things get better soon for you.

Hi mazza,

I know when my dose of Synthroid was high until I got used to it my heart would feel like it was beating faster, like anxiety. Is that what you mean? That does go away if the dose is not too high for you, I would think if it does not go away it could of been to high too fast. See an Endocronologist they should know best!

Dear Mazza,
I cannot tell what you mean by "severe anxiety attacks." Levothyroxine is the leading ingredient in Synthroid and it does indeed list general anxiety, irritability etc as potential side effects.
I absolutely agree that you should research every drug that you're prescribed and report anything concerning to your medical team.

Hello mazza123. I checked out this med and found that just googleing your question,came up with many different responses that all sound like yours.The 2 most common factors were, that people were asking if this med or the namebrand(Synthroid) can cause varying degress of anxiety because they were taking it,or had their dosage increased,and started experiencing anxiety,and, that their Dr's told them it was'nt the drug that was causing the anxiety.I looked at Wikipedia and found this information very easily. So, why not check it out there? I've found that if I want to know everything about a med to go there. You can find everything from what year a drug was made to the Pharmacokenetics of most meds. Highly helpful and you can get as deep in to that as one wants !!
I'm hoping somone else will have an answer,as this is a pretty common medication,and I'm sure some community members have experience with it.
tejas129