Thanks guys.  Funny he said blueberries don't do it all the time.  Maybe I will try the vinegar wash.  I worried about pesticides or mold, myself.  There was no visible mold and they were particularly good blueberries!  Most were nice and firm and sweet. 

He only has that awful month each spring for pollen allergies, maybe two months.  But has been good the last week or so.  I will just keep an eye on it.

My older DS who has no food allergies declared last year that raw blueberries "make my tongue twitch, like as if a battery was placed on it".  Well cooked blueberries are okay, he says.  He has really mild environmental allergies.  I've often wondered whether it was OAS or the blueberries were just too acidic.  He said bananas are ok though.

Benedryl will knock those symptoms down.  While not life threatening, they are very very uncomfortable.  DD hates the feelings so much that she will avoid all raw fruits and veggies that cause it.

One of my boys had issues like OAS with grapes so the pediatrician said stop for a year and be sure to have Benedryl when you try again.  He eats grapes all the time now.  She said she thinks it was the pesticide or whatever had been sprayed on the fruit to clean it when picked.

I use to wash berries and grapes with water and baking soda and a couple years ago I started using water and white vinegar.  Not sure if that made the difference for my son or not but it sure cleans the fruit well!

Here is some more information on OAS:
http://www.inspection.gc.ca/food/information-for-consumers/fact-sheets/food-allergies/oral-allergy-syndrome/eng/1332351950134/1332352076501

Whilst blueberries aren't on that chart, it could be possible that this is OAS.  Or, perhaps a sensitivity to a chemical or mould on the fruit.  If the problem persists, I would see an allergist to get an answer one way or the other. 

Most OAS isn't life-threatening.  Less than 2% of people with OAS experience anaphylaxis. 

I get an itchy mouth from raw bananas very rarely - it is irritating but goes away quickly.  My husband too, also very rarely.  I'm not allergic to ragweed, latex or bananas, so I wonder if there could be something about bananas that causes mouth/tongue itch unrelated to allergy - it's a mystery in our house too.

Here's hoping it's a one-off case for your DS and nothing more than an irritation.  Keep notes of what was eaten, when, and symptoms, just in case.

So, ds, who has no known allergies, is telling me he has an itchy or "weird" feeling tongue after eating a few blueberries.  He has had some from this same box earlier in the week.  Over the past few weeks or month, he has had lots of blueberries and not had this happen, he says.  He is not big on providing detailed descriptions, lol.  Then he added, "It is the same thing that happens when I eat bananas."  I have been a bit suspicious about bananas, because he had decided at around age 3-4 to declare an allergy to bananas and stopped eating them.  However, about a month or so ago, he decided he once again loves them and has eaten at least a few a week, with no mention of symptoms, until just now, when he compared the blueberries to the feeling he gets on his tongue from bananas. 

I honestly have no experience with oral allergy syndrome, other than I see others here mention having it.  Ds says he has not noticed this from any other foods ever, and only once before from blueberries, with a particular bag of the small, frozen wild blueberries from Trader Joe's, though he did not tell me then, only now. 

The itchy tongue lasted less than 5 minutes.  He had another snack, and it resolved.  But, I think it was particularly strong this time, which is why he mentioned it.  he was annoyed by it and scratching his tongue on his teeth, and sticking it out, etc...  No other symptoms, no swelling, no hives, nothing, and now it has resolved. 

How concerning is this?  Does OAS show with testing?  Is it something to carry epi for?  I am quite ignorant about it!  He does have pretty bad pollen allergies, but is actually over it this week.  he seems better than a few weeks ago.  Must be a specific tree or something, and once it passes, his pollen allergy is not so bad.