The scenario

Miranda Janus walks into the pharmacy, practically dragging her husband Andy behind her. "Tell him he needs to get this seen to," she implores pharmacy technician Vicky. "Look!"

Miranda pushes Andy round and Vicky sees a large crescent-shaped burn on the side of his lower leg. "Ooh, that looks nasty. What on earth happened?" asks Vicky, coming round to the other side of the counter and noticing that the skin is blistered and looks wet and greasy.

"I was getting the last bits of shopping out of the boot of the car when I caught my leg on the exhaust," says Andy. "It’s painful – who knew exhaust pipes get that hot? But I’m sure it’ll settle down in time. Perhaps you can give me a dressing or some cream to put on it? I’m sure there is something better than butter, which is what Miranda slapped on. I swear it has made it worse."