A Thai man was left horrified after discovering a tapeworm that he said measured up to 10 metres, coming out of his anus while using the bathroom.

According to reports, the man initially assumed the gruesome find was leftover from his surgery the week before.

The man from the Udon Thai region in northeast Thailand, who is also a photographer, shared the photos to Facebook with the caption, “Damn….. What’s in me?”

The man told local publication Khaosod he had just dropped off his children at school and was running errands all morning.

Later in the day, he went to the bathroom to relieve himself when he felt like something was coming out of his bottom.

The man when he started pulling at the tapeworm, not knowing what it was, described it as “ tough, straight, rubbery” and said it was “probably 10 metres long.”

The man recently had surgery to remove his appendix and initially thought perhaps the tapeworm was a piece of string.

“The first thing I thought of was not thinking about parasites,” he told Khaosod.

Tapeworms are intestinal parasites, which cannot survive on their own only within another organism, they live in the gut of humans and animals.

Tapeworms will usually enter the human host from eating raw or undercooked meat, according to Medical News Today, however, sometimes humans can become infected when coming into contact with animal faeces or drinking contaminated water.

Tapeworms can live inside a host for up to 20 years and can measure to be 50 feet long, and it is not uncommon for the parasite to pass through the human digestive system and end up in the toilet.

The man ended up flushing the tapeworm down the toilet when he was finished taking photos of it.