Years ago, I tested positive for an allergy to shellfish. I have never had a taste for it, so it hasn't been a problem. However, every time I complete medical paperwork, after seeing the shellfish allergy the doctor writes "no iodine" on my paperwork. Why? I have also noticed, that after eating salty chips or fries, my tounge feels bumpy around the edges and is slightly uncomfortable. Is there a relation to the iodine in salt? Thanks. Atlanta
Allergic to shellfish. Why iodine?
4/ 6/08 12:27am
Hi Babs,
I am no doctor, but it sounds like you had a drug interaction with the antibiotic and prilosec. According to gicare.com, prilosec might hamper the absorption of an antibiotic which would make it difficult for the antibiotic to work. You can also read about the medicines that are commonly prescribed for acid reflux here in the drugs database.
Are there interactions with other drugs?
An interaction generally means that one drug may increase or decrease the effect of another drug. Also, the more medications a person takes, the more likely there will be a drug interaction.
Interactions with this drug may occur with the following:
- diazepam (Valium)
- phenytoin (Dilantin)
- blood thinners (Coumadin)
Certain other drugs require stomach acid to be changed into their active form to be absorbed. Since omeprazole eliminates stomach acid so effectively, the absorption of the following drugs may be adversely affected:
- ampicillin (Polycillin, Omnipen)
- digoxin (Lanoxin)
- iron preparations
- ketoconazole (Nizoral)
If you take any of the above medications, ask your physician. It is okay to take antacids.
I hope this helps a little. Please stay in touch and let us know how you are doing!
Vicki M
4/21/08 1:09am
Hi Atlanta,
I am tuning in a little late but I wanted to clarify a couple of issues. Iodine allergy and shellfish allergy are not related. This has been a misconception for a number of years. I review allergy literature every year looking for a change in this position, based on research, but there has been no change. Shellfish does concentrate iodine when in sea water but the iodine is not the cause of shellfish allergy. Shellfish protein causes the allergic reaction.
When allergist test patients for allergy to shellfish whether by blood test or skin test, iodine is not involved at all. The most common form of iodine allergy we currently see is related to contrast allergy, associated with radioiodine preparations.
Unfortunately medical staff still question patients about allergy to iodine before infusing iodinated contrast but they are propagating a misconception. When I am called about this (less common now) I inform medical staff that allergy to shellfish alone does not require any further intervention when iodine contrast infusion is being considered. A history of reaction to iodine contrast or other form of iodine product (not iodized salt) would warrant special preparation.
Later in the follow-up comments you mentioned a concern you have about Prilosec, antibiotics and possible reactions to them. The symptoms you had suggest a drug reaction. I think you may be intolerant to both Prilosec and the antibiotic you had. Both medications should be avoided until you discuss this with a doctor, preferably a board certified allergist. Further exposure could result in a more severe or fatal reaction. There are different types of drug reactions you can have that may not be related to classic allergy or dependent on drug interaction.
Good Luck!
J. Thompson, MD
4/21/08 6:58pm
Thanks for the great detail. I will get an appt with an allergist soon. I asked my gen. dr. about it, and he blew off the need for it just like he did when I described my severe reactions to the two meds. (Time for a new DR!) I am in my 40s and until now have been VERY healthy, rarely needing more than annual checkups. Seems like it's time for a tune up. I just learned that I have several cysts on my liver. When trying to schedule my exams to look further into it, the same question was asked, "Allergies?"..."Just shellfish.." and I mentioned the two recent drug reactions. I received the same response as always, "Oh, well, then we'll have to do MRI with non-iodine contrast, rather than CT w/contrast." I never mention the iodine, they just always say that when hearing the seafood mentioned. I appreciate your information, which sounds like you've really invested a lot of research into it. I will see a REAL allergist as soon as I finish learning about the liver cysts. Thanks so much.
4/25/08 9:37am
Atlanta,
Thank you for your reply. I am glad you will be seeing a board certified allergist. He or she can assist you with future matters regarding the shellfish/iodine disconnection and drug interactions. I have called and written radiology departments through the years, to clarify the iodine contrast / allergy issue. You should not be denied definitive exams for the wrong reason.
Good Luck,
J. Thompson, MD
7/12/08 11:58pm
I would like to comment on the iodine and shellfish allergy issues, and ask a question.
I am 51 and at 18 had a most severe reaction (grotesque swelling, pus-filled rash, etc.) to iodinated contrast media for a gall bladder test. It was next to impossible to get any reliable information about this.
What I was told is that cretinism is associated with outright iodine ALLERGY, and that the correct term for my reaction is hypersensitivity. (Since I'm typing my own post here, I trust you can tell I do not have a subnormal IQ.)
After that, I avoided iodine. I did some amateur tests on myself with topical iodine preparations and they also created itching, swelling, and more disgusting stuff. I also have a dreadful reaction to povidone-iodine preparations (like Betadine) and have fought with nurses who tried to approach me with it when hospitalized (I pray I am always conscious enough to do this!).
The amount of iodine in salt is not enough to provoke a reaction, but I use natural seasalt anyway, for various reasons. One warning: multi-vitamins! The ONLY one I have found not containing iodine is Nature's Life One Daily Multiple/Iron & Iodine Free. Another warning: seaweed and kelp products, whether as food, in supplements or beauty products.
Anyway, all along I loved shellfish and ate a lot of it. At 49, for reasons unknown, I had a sort of two-week shellfish binge--it was all I wanted to eat. I started reacting with throat swelling, dizziness, bloating, redness and itching, but not in a life-threatening way. Some of these symptoms lasted for FIVE WEEKS. I felt like there was a propane torch under my skin and sleep was very difficult. I took antihistamines, but due to diabetes cannot have cortisone shots.
Two weeks ago I ate at my longtime favorite Asian restaurant. I order meat & poultry dishes and warn them to knock off the fish sauce (contains boiled-down shellfish). This time they obviously forgot. The amount of shellfish would have been micrograms, so the reaction was not as acute.
But two weeks later, my reaction continues to come & go in waves--this is what I do not understand, and would appreciate some clarification. As I type, my lips are tingling and my back & shoulders are covered with bloodied scratches, my feet and hands are swollen. I haven't seen another post that talked about duration of symptoms of a non-emergency kind. Like others who have posted, I am now petrified of all seafood.
Also, re Prilosec: I used to take this and am happy I weaned myself off of it, using the non-Rx products PhChoice and Twinlab Digestive Enzymes. However, while on it I was prescribed antibiotics and got the classic swollen joints w/ rash. I was told I have to now avoid penicillin, and read somewhere that taking antibiotics with Prilosec can indeed induce this reaction.
7/31/10 11:03pm
Allison I can certainly feel for you, here's my story may help someone
I am not sure whether or not all rh negs are allergic to iodine products or not?.. but are my facts.
My Mother was a AB- neg and couldn't tolerate iodine, if painted with it in surgery she swelled up like a balloon and stitches burst!.
I am a rh neg B blood group, my first recalL re iodine was getting to drink a white liquid at Taumaranui Hospital N Z for gallstone xrays yrs ago . it reacted very quickly, as I left I started scratching my neck at the itchy angry red welts and said this place must have fleas!!
Next morning my faced had swelled up like a balloon, my eyes virtually disappeared, I had aged about 30yrs overnight Doc gave me a pill, but I was so P**sed off I never went back again. So I have always made very clear to any Medical person, I would appear to have an iodine intolerace, its on my Medical records.
'(The radioactive isotope iodine-131 (see radioactivity), with an eight-day half-life, is very useful in medicine (see nuclear
Some X-rays need the patient to have an injection of dye to make the picture clearer. The dye may contain iodine. . It is important, however, to tell the person doing the X-ray about allergies and any reactions which have occurred in the past.)
On June 28/6/2010 I have had day bladder surgery, took about 20mins..home again I noticed a burning in the bladder quite painful and brown/yellow staining..and a strong chemical smell .most odd, this got worse and after 2 weeks started to bleed for three days with small clots , now rather worried and a bit angry I shot off to the local Dr, she didn't know and couldn't find out what they used, ( which I found very odd) so online I came across this info, so it would appear they may have used an iodine product even though it states on my records 'no iodine'
Providone Iodine Bladder Instillation for prevention of wound infection.
Povidone iodine antiseptic solution, surgical scrub 7.5%
Also very extreme cases, Povidone-iodine-induced burn: case report and review of the literature
http://www.ncbi.nlm.nih.gov/pubmed/17064209
29/7/2010 Waikato Hospital, NZ replied to my complaint re the burns, staining, chemical smell etc., and states" we believe the symtoms you have experienced are normal post-procedure events which are noted as likely to occur on our information pamphlet" ver odd as I have this procedure twicw before and no severe reaction like this , re burning, chemical smell and brown staining.
They also state the bladder was irrigated with 'GLYCINE..'..so I checked out Gylcine.
NB http://www.baxterhealthcare.com.au/downloads/products/cmi/glycine_irrigation_solution.pdf Product description What does Glycine Irrigation Solution looks like?
Glycine Irrigation Solution is a clear colourless solution that is packaged in a
Uromatic plastic bag.
.
The active component in Glycine Irrigation Solution is glycine. Glycine is a naturally
occurring amino acid, and part of all proteins, and is a normal component of the
human diet. It is dissolved in Water for Irrigations
Conclusion mine is, that some chemical reaction caused the continuous burning, chemical smell, brown staining and post operative bleeding commencing after a time lapse of 2 weeks, that by information re drugs online, if seems highly improbable that GYLCINE is responsible for the severe reaction after bladder irrigation . That Povidone/ Iodine may been used in error is highly probable and would explain the severe symtoms described as above...
So anyone who has an iodine reaction, stand up for yourself, tell them all the time and get an iodine allergy bracelet, thats next on my list! or have a tattoo on my stomach..rh neg B Allergy IODINE!
and best of luck!!
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Hi Atlanta,
It sounds like you have an allergy to the iodine products in shellfish and in many other parts of our daily lives including MRI's and Cat Scans. There is a conversation here that was started by Crab Wary, where lots of folks in the same boat as you realized they had an allergy to iodine by finding out they were allergic to shellfish. Some found out the hard way!
There is a section here about drug allergies that also says the second most common allergy after penicillian is iodine common in most contrast procedures like xrays and such. You can read the entire article here.
I hope this helps. You are not alone in this!! Stay in touch and let us know how you are doing!
Vicki M