guinea pig ate nerf dart!

Question
Hello.  My son's guinea pig (the pig is approximately 1 year old) ate a Nerf Dart on Christmas Eve!  (Not the plastic part, but ALL of the foam.)  I just heard back from the manufacturer, and was told that the foam is NOT digestible.

Our pig is acting fine, eating, drinking, going to the bathroom.  He is his normal happy self, popcorning and responding to our family just as he always does.

However, knowing that the foam is non-digestible has us worried.  Is there anything we can do?  Even though he's fine now, we're worried sometime in the near or far future this can be a serious problem.

If you have any advice, it is greatly appreciated!

Thank you so much!  

Answer
Hello,
As long as he poos it all out and doesn't show any signs of being lethargic, not drinking water or eating then he should be fine. It may not be digestible but as long as it goes through his system and doesn't get stuck anywhere he should be fine. Check his airways are not clogged up, if he shows any signs of pain then take him immediately to the vet. As I said before as long as he poos the dart out (you could check his droppings) then he shouldn't have any problems in the future.
I have had a guinea eat half a plastic bag and she pooed it all out and is fine so don't be too worried.
Sorry I took so long to reply and I hope this helps