I suffer every three weeks or so from diagnosed chronic sinusitis for about 2 years. Pain round my eyes, head, painful to breath through my nose. I also have an underactive thyroid and still have symptoms ( constipation, brain fog, tiredness etc) all the time and get worse when my sinuses do or other the other way about even though the doctor says they are unrelated, I believe they are. Last March I felt run down with both of the above and blood tests showed I had swung from under to over tsh 0.6 and t4 23.9, 5 weeks later blood tests were tsh 4 and t4 16.9. Frustration with my doctor has stopped me from going back to docs even though I feel lousy 90% of the time. But last month I gave up and went back, this time was given 2 week course of antibiotics for my sinuses, ANOTHER nasal spray and antihistamines. I blubbed like a baby to the doc because I can't handle it anymore. I managed to go a full 4 weeks before another episode. Another prescribed course of antibiotics and nasal sprays and this time my blood test showed my tsh is low at 0.5, don't know my t4 but I haven't spoken to my doc cause she hasn't looked at my results yet. Why do I keep swinging under to over? I take the same 150mc every morning before eating. I can't afford private blood tests or medication and doc won't test t3.
Swinging from underactive to over?: I suffer... - Thyroid UK
Swinging from underactive to over?
Littlejen, TSH below range and FT4 slightly over range don't mean you are overmedicated as long as FT3 is within range. Unless you feel overmedicated on 150mcg there's no reason for dose to be adjusted. Read Treatment Options in thyroiduk.org.uk/tuk/about_...
Thyroid levels fluctuate for a number of reasons:
1. Reducing dose because TSH is low, then raising it when TSH rises. If this happens regularly fine tweaking the dose in12.5mcg increments can be helpful ie 125/150mcg alternate days.
2. If you have autoimmune thyroid disease (Hashimoto's) this can cause fluctuation, usually causing FT3 to rise and TSH to fall when thyroid cells dump hormone as cells die off.
3. Some antibiotics increase uptake of Levothyroxine, while others may reduce it.
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I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.
Thanks, I wasn't aware that antibiotics affected the uptake of thyroxine and I seem to only had symptoms of being over active since I have been taking them this time, although I wasn't in the past when my tsh dropped. I don't know if I have Hashimito's as my doctor has never mentioned it, although I have suspected for a while. To be honest I find it difficult to understand my test results and doctors haven't been a great help.
Littlejen, if you feel overmedicated on 150mcg try 125mcg or 125/150mcg alternate days while you're on the antibiotics.
_______________________________________________________________________________
I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.
I think you ought to get hold of as many test results as possible and post them on here. Doesn't sound as if your doctor has much idea what she's doing. You need to know exactly what was tested when and what the results were. Only then can you start to take charge of your own health. 
How many test results should I ask for, just the last lot or the last 2 or 3?
I have a constant problem with my sinuses not long finished a course of antibiotics but it hasnt cleared it up constant headaches bleeding nose .Doctors never admit that hashimotos/thyroiditius can cause problems with other body functions .Hope u find answers soon it can be very frustrating not knowing whats happening to your body
I think am going to look into doing an elimination diet to see if there is anything I am eating that's contributing towards my sinus problems. I have also been referred to ent but there is a 13 week waiting list. I am also going to ask for my full blood test results and put them on here as I was advised by Greygoose, but should I just ask for my last set or maybe the last 2 or 3 sets of results?
Ive seen a ent specialist years ago put a camera up my nose told me to use nasal drops twice a day .When i was young i had my sinuses scrapped and burnt have always had problems but its the headaches that have got very painful then my nose bleeds seems to relieve the pressure for a little while.Hope u get to see ent soon
I don't get nose bleeds but I get pain round my eyes and cheeks, face feels hot, constipation, extreme fatigue and pain breathing through my nose and either one or another nostril becomes blocked. Going by past tests my tsh level drops when I feel like this. And now I have horrible palpitations that won't shift. I'm not holding out on the ent solving my sinus issue because I think there is more to it but I've got to try something.
Dear littlejen this is such a sorry tale, I do hope someone here can help you.
If you PM me, as I guess it's not allowed to put my website address on here, I will give you a link to the site because on there is a method for clearing the sinuses and keeping them clear which also seems to stop the sinusitis. (It also helps indigestion). Then you wouldn't need the antibiotics.
Sounds to me like you are having flare ups with your levels due to something that you are doing that is constant and periodic where this seems to be happening..like food or vitamin deficiency. Or gut deficiency. From what I have learnt from others here, a food reaction like gluten or a vitamin deficiency could be the reason for the drastic swing. What I know about is gut health. You are taking loads of antibiotics. Are you replacing the good gut bacteria in your gut? Have you checked whether you may not have a candida overgrowth (I think there is a simple spit test you can do)..there is a big link between gut and thyroid I am realising. For years I had the gut issues and no thyroid issues.
Also have you thought about testing specifically for vitamin d and taking and really high dose supplement? 6000iu for instance? Recent tests have shown that there is basically no limit to how much Vitamins D3 you can take and that it is critical for the immune system. This could have the dual effect of helping you fight the sinus and boost your thyroid.
Finally alternative therapies specifically acupuncture have been shown to assist with a lot of pain related and immune related issues. It's worth a try. Depending on where you are based I know of an excellent acupuncturist. Pm if you are in London.
25 mcg hasn't had much of an impact at all
Has selenium supplement helped t4 to t3 conversion?
went from under to overactive? Or just over medicated? 
Swinging Thyroid results
Grave's disease but Underactive??
