Dr B. Loony makes his rounds at hospitals with an aim to infect patients with laughter. Credit: Ninemsn.

Jean-Paul Bell also known as Dr B Loony, the clown doctor who co-founded the charitable organization which brightens the lives of child patients across Australia, says those in hospitals were usually itching for a laugh.

When you're in pain and suffering ... it's not like the last thing you want to do is have a laugh, said Jean-Paul Bell.

You'll grab a laugh instantly just to escape where you're at - humour has that effect where it gives you a brief out-of-body experience.

A founder of the Humour Foundation alongside a real doctor, Dr Peter Spitzer also known as Dr Fruit-Loop, in the late 1990s, Mr Bell says the service has now grew to nearly 70 clown doctors.

They - red-nosed, lab coat-wearing pranksters have become a common sight in children's wards, where they shared sleight-of-hand tricks and slapstick gags.

A clown doctor's job can include making a balloon hammer for a sick child to meter out some justice, or a festive re-decoration of their beds with toilet paper.

Although focus is given on children, parents have been aimed to release the pressure valve too.

Mr Bell recounts that some of his most serious clowning - or embedded humour therapy - was done is the children's burns unit.

He said, To reduce pain by distracting a child is a great skill.

It does take a little bit of lunacy at some times ... to get them to a state of half-crying, half-laughing.

Mr Bell has authored a book sharing the experiences of being a clown doctor with his colleagues Australia-wide and the book, Laughter is the Best Medicine, which is published by Hachette Australia, is in stores now.

April 1, Thursday is Smile Day, the major annual fundraiser by the Humour Foundation. Donations can be made at www.smileday.com.au.