My niece used to hold her breath and faint up until being about 3/4. She first did it at the supermarket when she couldn't get something she wanted. My sister called the ambulance because she was so scared, but after going to the hospital they told her that she had just fainted as she had gotten so upset.

I am afraid my niece worked out this was the ideal way of getting her own way because my sister when she was having a tanty (depending where she was having one) had to be close by to catch her when she fainted and hold her till she came round or give her what she wanted if it could be given.

Eventually she grew out of it but that didn't stop her trying to faint though for a while after to get her own way. She is 9 now and is very demanding. We tried many different ways to avoid her holding her breath without giving her what she wanted all the time but it is very scary when they do it. In the end they get ultimately what they want in either situation your attention.

Sorry I can't tell you how we stopped it. We just had to let it run it's course. Just for your peace of mind as the others have said take him to your GP and see if there is something they can recommend.