Could this be teething

[imsuchafool12345]

My son for about 4 days has had diarrhoea. I thought at first maybe it was something he ate (as we're trying him on anything and every he's allowed to have - not milk or egg as he's allergic to those) but still has diarrhoea. He's still his normal self crawling trying to stand shouting talking away. I think it's teething as he was like this last time but not as bad. I just phoned the doctors and they're fully booked for 2 weeks so I'm going to get his dad to take him to the walk in tomorrow. Would it be a good idea to give him dioralyte till I know what's going on?