A morbidly obese teenager is seeking medical help to walk again as his extreme weight has left him bedridden.

Sangtawan Wantha, 16, had to quit school when he ballooned to a whopping 29 stone (403 pounds).

Once an ordinary Grade 9 student, the youngster now spends his days bedridden as his legs had suffered debilitating nerve damage. He is completely dependent on his struggling mother, Duangdao Thaworn, 52, for even basic tasks.

Footage shows the devoted parent wiping down the teenager with a wet cloth before dousing him in baby powder.

For months, the pair have been living in grinding poverty in their squalid house in Nakhon Phanom, northeast Thailand, after Duangdao quit her restaurant cleaning job to take care of her son full time.

She said: 'Every morning I clean and wipe his body, and I help him with his physical therapy just like the doctor told me. When he needs to go, I just lay an oversized diaper on the floor because even the biggest size wouldn't fit him.

'We only have three appliances in the whole house: a fan, a rice cooker and an electric pan. Some days we can't even afford food, so I have to ask our relatives for help.'

The single mother added that Sangtawan's weight has made travelling to Nakhon Phanom Hospital difficult. The hospital's X-ray bed could also only hold 220 pounds, leaving doctors unable to properly examine him.

Somchai Chomphukham, chief of the provincial public health office, visited the pair on November 6, after Good Samaritans sought help for the pair.

They allegedly found that Sangtawan had 'no serious complications'.

The teenager was scheduled to receive intensive physical therapy at the That Phanom Crown Prince Hospital to reduce his weight and help him move again.

Doctors said he may undergo gastric bypass surgery if he remains morbidly obese.

A grateful Duangdao told reporters: 'I'm so grateful to see so many agencies reaching out to help my son. I don't wish for money, only for him to return to a normal life, to walk and move like everyone else. Thank you to everyone for your support. It gives me hope that he'll be able to walk again.'