Hi folks I’m a little worried I’m having a CT scan with contrast in a few weeks to look at my abdomen stomach (hiatus hernia) gastritis and liver cysts all need checking but once a gastroenterologist said to me because I’m anaphylactic to shellfish / seafood I may be allergic to Iodine ? The contrast in the injection for the scan has iodine in it now I’m panicking incase I have an allergic reaction ? If I have the scan without contrast the pictures are not as clear ? Does anyone know whether i should have this was the gastroenterologist being over cautious to suggest that ?
Any advice would be much appreciated
Kazbe 🙂
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Kazbe
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Hi Kazbe. They will tell you the scans won’t be as clear but that’s more for their convenience than yours.I was told by guy doing scanning that because I’d refused to have the contrast for my scan that it has been known for the radiologist to sit on the report because I was being uncooperative,I said to him you sound as if your actually threatening me so I will be advising my consultant haematologist of this conversation which I did.
It’s your decision at the end of the day but I’ve had a brain scan and 2 abdominal ct scans and they very clearly showed the issues I had so don’t be bullied into anything if you feel you have valid reasons for not having it.
I will take that on board I just don’t like the idea of having an injection that could cause a serious reaction gives metallic taste in the mouth hot weird sensations and it is bad for the kidneys too I would imagine ? I’m sorry you had a bad experience from the radiologist that’s awful he should of been reassuring you when you’re feeling so anxious
Hi kazbe it’s not nice when your already Ill and scared of what they might find ,all they want to do is get you to sign that piece of paper and that covers their arses when it all goes wrong.You stick to your guns there’s varied opinions on this subject,I just knew I’d have a reaction and I’d no intention of having the contrast but Dont prewarn them just turn up on the day and refuse it if you choose to.take care good luck x
Althrough not allergic to iodine I had an adverse reaction to iodine based contrast. They had to stop the scan and administer some meds before another scan could be done. Overall the expierence wasn't pleasant. I'd avoid the contrast
Oh dear that sounded awful for you , this is what I’m afraid of I think il just have the scan without contrast the more I hear the more it scares me ☹️
I used to work as a radiographer (the person doing the scan).
Before they do anything, they should run through a series of questions with you - one being are you allergic to shellfish. As you rightly say, if you are, then you could be allergic to the iodine. Therefore, they could either use a different contrast, or run the scan without contrast.
Now, the contrast is used to look at the blood flow within the area they’re looking at - in your case, your abdomen. A barium sulphate contrast only looks at the structure of your gastrointestinal system - so the outline of your oesophagus, stomach, large and small intestine and rectum. It does not show the blood flow.
So, they could run the CT without the contrast, as this would still show liver cysts, hiatus hernia and other abdominal structures.
If they particularly wanted to see the blood flow, they could re-book you for an MRI scan instead.
I am very sorry that you have had previously negative interactions when having a CT scan. If this ever happens again, please ask to see the CT head of department, or senior radiographer & complain. If they do something without your consent, that is considered assault.
Finally, the contrast is excreted by the kidneys - it only becomes a problem if you have a reduced kidney function (eg on dialysis, or only 1 kidney working).
If you have any queries at all, please feel free to ask me. You should not have to put up with such an awful service.
If one had an MRI instead do they then insist on gadalonium contrast? And is this not possibly more problematic, with all the lawsuits against it in the states as it can cause fibrosis etc? I have just refused this and they were not happy, but they did not say if my MRI result was as good. But as I had flu at the time and was coughing for most of it, I guess that might have altered the images and results?
I was asked if I had any allergies ,no specifics . Did not have any.Had no problem with contrast . Some think the iodine could affect the thyroid but as it is excreted it seems unlikely.
Many years ago I had a liver scan and I had an allergic reaction to the dye they injected and I started itching all over. The Doctor injected me with something to stop it and he said some people can have a reaction and it might have been because I suffer from hay fever.
I have hay fever too and wondered did you have the iodine contrast or other? I just had CT with iodine and I think my TSH has plummeted to 0. something so am about to re test. My mother had iodine contrast and her blood pressure shot up to 300 over 200 so they had to give her emergency tablet antidote.
I was in the same dilemma as you in January. Booked in for CT colonoscopy with contrast. I’m Hyperthyroid and had a reaction last time to my iodine uptake Scan. In the end after due consideration they did the CT without contrast, just Buscopsn. Everyone was very kind in the department and I felt really considered and safe.
Best to tell them your worries with the tick questionnaire beforehand.
In the last 2 years I've had 2 CT scans with iodine contrast. The first time I had abdomen scan, so I drank the solution with the contras. The result: my TSH jumped from 3 to 21 (I'm Hashi hypothyroid on Euthyrox). The second time I had CT scan of my lungs, so it was iodine IV contrast. The result: within minutes after the injection I got urticaria all over my face, difficulties with breathing, which would probaly converge into anaphylactic shock if hadn't been given few shots of fast and slow releasing antihistaminic. Also, my TSH jumped again from 2 to 10 ("only" 10 becouse my endo had been preparing me for the procedure by giving me higher doses of Euthyrox 15 days prior to CT). The only question I had been asked before the procedure was if I were alergic to strawberries.
So, I don't want to scare you, but since I had never had any specific reaction to anything (only mild seasonal hay feaver), I just want to warn you to check if it is really necessary to get iodone contrast for this particular san.
I was supposed to redo the lungs scan 6-9 months after the first one, but I still haven't becouse I don't want to go through all that mess again. So I'm searching if there is anywhere in Europe any type of less agressive procedure. I would be very gratefull if anybody could suggest the procedure or clinic...
Thankyou for your detailed experience and I’ve decided I’m not having contrast for my CT scan I’ve contacted my consultant and asked if he wants a more detailed scan il have to opt for an MRI because now I’ve heard all these adverse effects I’m not prepared to take that risk !
Could you ask for an MRI of your lungs rather than the CT after your awful ordeal ? I hope you can have that as an alternative that would eliminate any bad reaction and also get the results you need .
I had a radioactive iodine injection for an isotope x-ray in 1970 for an overactive Thyroid Gland and had no reaction.In 2016 I had a CT angiogram with iodine contrast but this time I had a burning hot poker-like feeling in my heart, itching that turned into hives and couldn't breathe. They had to stop and I was put on antihistamine and steroids and oxygen.
Never again!. Think I screamed when it began. It was a while before I could go home.
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now I’m panicking incase I have an allergic reaction ? If I have the scan without contrast the pictures are not as clear ? Does anyone know whether i should have this was the gastroenterologist being over cautious to suggest that ? 
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