Log in
Thyroid UK
91,651 members105,958 posts


Can anyone confirm what type of iodine is used in levothyroxine? I use povidone iodine (diluted) on my dog sometimes for itchy skin from mowed grass. After much research one site listed active ingredient in Levothyroxine as povidone iodine? Povidone I always thought was what medical staff use as topical antibacterial reasons. Why are we ingesting a form of iodine not recommended for ingestion? Lugols and some other oral brands have a very small amount of povidone iodine...I was just wondering why this is? Thanks.

6 Replies

Are you absolutely sure? Did it not just say "povidone"?

This was asked some time ago and the answer was that povidone was used as in ingredient - not povidone iodine. But quickly scanning a list, it is easy to miss the difference.

The other iodine content of levothyroxine is simply the atoms that constitute levothyroxine. Four atoms of iodine in each molecule of levothyroxine.


Thanks for reply hel...

I was looking at posts from 'inspire.com'

One post stated:

I asked the mail order pharmacy, where I get my medications, including L- thyroxine (synthroid) contained iodine or red dye. I was told that the L- thyroxine contained Povidine (iodine)."

Another post stated "povidine free levo" is available.

These posts date back to 2009. It's all a bit confusing trying to pin down exact compounds in Levothyroxine!

Was also wondering about GMO in corn starch fillers?

Thanks. This site is so informative...makes you feel you're not alone!

I take 50 Levo.




Look up Povidone in Wiki .Then look up Povidone -iodine.

The former is used as a binder that ( according to Wiki) passes through us.

1 like

Thanks Treepie

Doh...that will be my first port of call from now on!


I think that poster has made a simple mistake.


You may also like...