Shellfish Allergy?

[SlyAnimal]

Hi All,
On Thursday I went out for dinner with some friends, we had some fried chicken, steamed fish, a spicy oyster salad (I only had 1x oyster though), deep fried larb and som tum Thai. The restaurant was one we'd never been to previously.

That night I had a sore stomach and trouble sleeping, then in the morning I found that I had a rash all over my body (except not on my face), although it's only itchy on my hands/feet. I went to the doctor that morning, and they said they thought it was an allergy.

Out of personal preference I don't usually eat seafood, but have never had any problems with eating seafood before.

I've read that apparently allergies can come on like this, where you become allergic to something which you have previously eaten without any problems.

None of the others suffered any ill effects from the meal.

But since I only had 1x oyster, and don't have a history of problems with seafood, I'm a little bit unsure on whether it was the oyster, or the fish, or perhaps something else which they mixed in with the food. Or that perhaps it was just that the oyster/fish had been exposed to a particular algae bloom or maybe the oil spill, and that that's what I'm really allergic to.

Are there tests which I can do, to check what I'm specifically allergic to? Other than eating a plate of oysters and seeing what happens lol, as I don't plan on going through this experience again (the itching has been driving me nuts! not to mention that I feel like I'm a leper )

Also, I turned down anti histomene tablets yesterday, as the doctor said they'd make me drowsy (And I needed to finish teaching my students before their exams next week). Although this was under the expectation that my allergic reaction would die down / go away within 12-24h, as I figured something I ate on Thursday, would have definitely passed out of my system by then. However it's now the following day and I've still got the same symptoms (Although perhaps slightly less than at their peak). How long do the symptoms of an allergy usually last for?

[Sheryl]

Can last for a few days easily.

There are antihistamines that do not usually cause drowsiness:

- cetirizine (Zyrtec or countless locally made generic equivalents)

- loratidine (Claritin/clarityne or many locally made generic equivalents

Can get at any pharmacy. Read the label to make sure it is only this and not mixed with something else as these same drugs are also used in combos.

The som tam thai may have had crushed crab in it and almost certainly had crushed dried shrimp, so the oyster would not have been the only shellfish you consumed.

Allergy to either shellfish, MSG or other food additives would be my guess. While you have undoubtedly consumed MSG here before and possibly other additives that may have been in last nite's meal, restaurants vary in how much they add and this can make a difference.

Of these possibilities, shellfish is probably the most likely. Shellfish allergy is usually quite distinct and limited to shellfish i.e. most people with it are fine eating fish, just need to avoid crab, clams oysters and the like.

Allergy aside, the dried shrimp added to sam tum, pad thai and many other Thai dishes contains a harmful red dye and is not at all good for you, and the raw crab often added to sam tum often carries liver fluke so it would really be in any case a good idea to try to avoid these in future.

You can if you want see an allergist for skin tests to try to find out if you are indeed allergic to shellfish.

Important: People who are allergic to shellfish are at high risk for serious adverse reaction to the contrast media used in CT and MRI scans. There is an alternative low-osmolarity medium that can be used instead for such cases, but only if the hospital knows of the possible seafood allergy. So unless you get definitive proof that you are not allergic to shellfish, should inform doctors of it especially prior to ever having a CT or MRI that involves contrast media. (They should ask you, but the "mai pen rai" philosophy sometimes gets in the way of has a standard medical precautions here, so speak up).