Lorna Fitzgerald, who plays Abi Branning in BBC One’s EastEnders, reportedly bought four balloons filled with nitrous oxide (also known as laughing gas) from a street dealer at 4am on Saturday.
The actress and a friend were then spotted inhaling the substance outside a London nightclub, and photographs of the incident were released in a morning paper.
Hippy crack makes users light-headed by starving them of oxygen. And, despite the fact it is legal in the UK, it has been associated with 17 deaths since 2006.
Now Lorna - according to soap insiders - faces a grilling from soap bosses.
READ MORE: Everything you need to know about EastEnders actress Lorna Fitzgerald
Speaking to The Sun, they said: “EastEnders really aren't happy and are going to be talking to Lorna about it.
“They don't take this kind of behaviour lightly.”
Another source added to The Mirror: “Lorna will be called in this week for a meeting with soap boss Dominic Treadwell-Collins to find out exactly what has happened.
“He will want to get to the bottom of it.”
Meanwhile a spokesperson from drugs charity the Angelus Foundation condoned her behaviour, saying it was “worrying” how “fashionable” the dangerous craze has become.
They have claimed that Lorna had put herself in danger, as she inhaled the drugs alongside a main road.
Lorna Fitzgerald or EastEnders bosses have yet to comment on these reports.