Ben, of Catherine Field, is anaphylactic and an allergic reaction to peanuts can kill him within 10 minutes if he doesn't have his trusty EpiPen treatment or medical help nearby.

His dad, Camden councillor Peter Johnson, has joined a group of men planning to run 22kilometres in the Sydney half marathon in September to raise money for allergy research in Macarthur.

Cr Johnson will be joined by Ben's clinical immunologist Brad Frankum, Camden Mayor Chris Patterson, Sergeant Mick Holmes and NSW MLC Charlie Lynn on the run.

When asked what effect his allergy had on everyday life, Ben said: ``I barely get to eat anything and I'm not allowed to share any food.''

But Cr Johnson paints a more severe picture. ``A peanut butter sandwich is more dangerous to Ben than a brown snake,'' he said.

The average person thinks all that will happen to Ben is he'll swell up or something. They don't realise he could die in 10 minutes. He carries an EpiPen everywhere he goes because of the urgency. ``He doesn't have an hour to get to hospital like you do with a snake bite you've got 10 minutes.''

Ben went one step further with his dad's analogy.

``It's kind of like bringing a death adder to school and letting it go in the middle of the school,'' he said.

The Johnson family is hoping that joint research by Campbelltown Hospital and the University of Western Sydney will lead to a cure or better medication.

Details, donations: Macarthur Lions Club, 46557116 or bernie1@bigpond.net.au or PO Box 377, Camden 2570. Donations must advise the funds are for allergy research.