This is the heartwarming moment a loyal dog was found patiently waiting for hours outside a hospital for its sick owner to return.

Two-year-old Nongdam, male Rottweiler and Dachshund mixed breed, followed his sick owner who was rushed to the emergency room in Ratchaburi province, Thailand on December 14.

The dog's owner, Pattama Hunsuwan, 41, had severe stomach pain after dinner and went to the hospital around 10 p.m. with her boyfriend.

Their pet was with them in the car and followed them to the hospital, but the couple had forgotten about the dog when they checked in for treatment.

Animals were not allowed inside the hospital so after being separated with its owners, Nongdam stood outside the entrance without leaving the spot all night.

One of the nurses on duty, Passorn Onsanit, said she thought the dog would eventually leave but it did not move out of the same spot, while its owner stayed in overnight.

The nurse said: ''The dog did not make loud noises or bother people. I thought it was a pet dog so I asked people to come and help it since I was on duty.

"I was afraid that it was lost or separated from its owners but when we tried to take it to another place it would not budge."

Since the dog refused to go with the nurses, they left it waiting until its owners found it when they were discharged the next morning.

Pattama thanked the nurses who watched their pet while they were away and went home with their loving dog.

She said: "When I am in the store, Nongdam will always help me find customers by barking. Nongdam is always a clingy but lovely dog.

"When I am not at the store, but someone enters, it will run to them and greet the customers sweetly."