Parrish Brown claims to have been "stoned" by a McDonald's iced tea (Image: Shutterstock)

One man claims to have remained "high as a dragon" after drinking an ice tea from McDonald's that contained weeds.

24-year-old Parrish Brown claimed that an employee on a transit in Hilton Head, South Carolina, US, had strangely said "extra lemon" when they bought the drink.

He said he ordered a 10-piece box of chicken nuggets, a double cheeseburger, and a sweet tea with light ice and extra lemon.

But he immediately noticed that the drink tasted different when he took a sip and said he continued to drink it because he was thirsty.

To his shock, as he removed the lid, Parrish saw three bags of weed in the cup.

He said, "I've never had weed drunk one day in my life, so right after I started drinking I felt weird and it did not taste like something I recognized."

Parrish Brown claimed his McDonalds iced tea was strewn with weed bags (Image: iStockphoto)

"I was up and in a panic and at work, so I called my dad. I did not want to get in trouble for that. "

The authorities have launched an investigation into the incident, stating that marijuana has been used as evidence and will be destroyed.

At this time, no arrests were made.

A representative from McDonalds said the company was working "fully with law enforcement agencies over the validity of this claim".