synthroid dose

[leealee]

I have been on .125 mcg of synthroid for 13 days post RAI.  I am still extremely constipated and was just wondering how long it takes for synthroid to kick in and your levels to come down.  After RAI, my TSH was almost 100.  I am also experiencing lower back pain and I don't know if this is due to the constipation of being hypo.

I had a colonoscopy in January of 2006 so I really don't believe the lower back pain and constipation is related to a GI disorder.

[Mark Lupo, M.D.]

It may take at least 3-4 weeks to begin to feel normal again after withdrawal from thyroid hormone.

[cosmicsoul]

Usually takes about 2-3 months to feel better and years to get your dose adjusted. Hang in there.. try other things for constipation in the meantime like fiber and fruits and vegetables. Good luck!