The promotional hashtag #McDstories, launched as part of a campaign for paid-for tweets to appear at the top of search results, spectacularly backfired as users used it to document their alleged horror stories of the Golden Arches.

Opponents accused McDonalds of making customers vomit, serving pig meat from gestation crates and serving burgers containing a fingernail. One fierce decrier claimed he would rather eat his own faceces than visit McDonald’s.

An initial hashtag #MeetTheFarmers, promoting the coorporation’s guarantee of fresh produce, concentrated on wholesome stories about farmers.

McDonald’s tweeted: “Meet Dirk Giannini, McDonald’s lettuce supplier, as he shows u his life on the farm #MeetTheFarmers”

But further tweets issued by McDonald’s marketing whizzkids contained the more general hash-tag #McDStories.

One of its tweets proclaimed: “When u make something w/pride, people can taste it,’ – McD potato supplier #McDStories”

However, within minutes, the tweets began to go radically off message.

@jfsmith23 wrote: “Watching a classmate projectile vomit his food all over the restaurant during a 6th grade trip. #McDStories”

One of more vitriolic was @MuzzaFuzza who wrote: “I haven’t been to McDonalds in years, because I’d rather eat my own diarrhea.”

Another followers, @nelo_taylor chimed in with: “These #McDStories never get old, kinda like a box of McDonald’s 10 piece”

Social media director Rick Wion told “Within an hour, we saw that it wasn’t going as planned. It was negative enough that we set about a change of course.”

“As Twitter continues to evolve its platform and engagement opportunities, we’re learning from our experiences”

Images: Getty/Twitter