Thyroid Disorders Community
26.1k Members
Avatar universal


how does Hydrochlorothiazide  interfere with the results of a thyroid test? I see that it can interfer, but how. does it change the results of your tsh
9 Responses
314892 tn?1264623903
I looked it up as well. There was no explanation, just that it does interfere with thyroid testing.
Have you asked the doctor?
Avatar universal
I try clicking on the ask a doctor and it won't let me . how do i ask the doctor
314892 tn?1264623903
On the forum, it is sometimes hard to get in and I see that questions aren't being answered lately. I don't know why. Sorry.
Avatar universal
I'd be curious as to the answer too.  I hadnt heard this, but I have been on hydrochlorothyzide for some time.  My thyroid is enlarged and I have many symptoms, but they have always said my lab results are within normal limits.   i was never told to stop this med before any testing.   Due to the enlargement, my doctor now has me on a 3 month trial of low dose synthroid too see if it will shrink the glad and help symptoms.  I have been on it for about 10 days now and really feel its helping, especially with the extreme fatigue I was having.  
Avatar universal
I still haven't found an anwer yet . if someone could it would be nice to know. My lab results are always flipping back and for between normal and borderline and the endo will not give me any meds because of this. I too want to know if this is what could be causing this.
Avatar universal
This is a few months late, but I believe I know the answer to this. HTCZ increases the amount of lithium (yes, we all have lithium in our bodies, it's not just a drug for people with bipolar disorder) in your system. Increased levels of lithium have been known to interfere with thyroid function. So, your TSH is probably going to be higher on HTCZ.
Avatar universal
um... seriously ignore my last post. I was thinking about 2 things at once, and for someone with brain fog, that's never a good thing. We do NOT have lithium in our bodies.
369861 tn?1306275686
I have never heard this and I am very curious since I have taken  hydrochlorothiazide  for the last 2 years.   As look up information, I noticing that if you have asthma/allergies not to take this med.  No one has said not to...

I'm baffled. I tried to look for anything that would answer this question and to my amazement, nothing does.

Looks like research is very much needed
Avatar universal
A brief history...1960's had 3/4 of my thyroid removed due to multiple nodules, put on iodine(I think), jump to now and I have 3mm pituatary nodule(not growing), multiple nodules on what is left of my thyroid with enlargement, been tested and retested and everything comes back WNL.  However, I have trouble sleeping, dry skin/hair, loosing hair, early menopause, fuzzy thinking, headaches(migraines), fatigue, increased difficulty losing weight, muscle cramps and frequent muscle aches(on meds for arthritis), irritability etc.  All seem to be symptome of hypothyroidism, yet my endo will not even try a low dose synthroid. I am taking Diovan HCT and the few things I have read, say it can skew the results.  I am at my wits end in trying to feel better.  I know it is my thyroid, but cannot get doc's to listen.  Any advice?
Have an Answer?
Top Thyroid Answerers
649848 tn?1534633700
Avatar universal
1756321 tn?1547095325
Queensland, Australia
Learn About Top Answerers
Didn't find the answer you were looking for?
Ask a question
Popular Resources
We tapped the CDC for information on what you need to know about radiation exposure
Endocrinologist Mark Lupo, MD, answers 10 questions about thyroid disorders and how to treat them
For people with Obsessive-Compulsive Disorder (OCD), the COVID-19 pandemic can be particularly challenging.
A list of national and international resources and hotlines to help connect you to needed health and medical services.
Here’s how your baby’s growing in your body each week.
These common ADD/ADHD myths could already be hurting your child