Swimming teacher Chloe Birch was visiting her boyfriend Robbie Harrison last Saturday and they went for a meal and then to nightclub Lost Bar and Club in Chorley.
Chloe, from Liverpool, said: “We went out with a few friends for a meal and arrived at the Lost Bar around midnight.
“We went downstairs and it was quite quiet.
“We went upstairs around 1am and were drinking and having a good time when all of a sudden I felt a sting in my arm which felt like someone had put a cigarette out on my arm.
“I knew exactly what it was. I passed out in the taxi on the way to the hospital.”
Two days after being jabbed she says her arm is aching, she has been vomiting all day, has a headache and is lethargic.
The Lost Bar and Club has been approached for comment.
Robbie’s dad Phil Harrison, from Adlington, contacted the Guardian about the incident.
He said: “Please could we encourage anybody with information which could assist police enquiries to come forward.”
He said of the police support: “To be honest they have been incredible so far
“As it’s the first case and hopefully the last they are making it top priority.
“We just want to make it public, as someone might know something.”
Chloe who studies Sports Therapy is now awaiting blood results.
She added: “It has put me off going out anywhere.
“You don’t think it’s going to happen to you. “The amount of people getting spiked at the minute.
“I’m lucky I was with Robbie as if I was with the girls it could have been worse.”
Lancashire Police - who took her clothes for evidence and pictures of her arm - confirmed that investigations are ongoing.
There has been a worrying trend of so-called “spiking” in recent weeks.
Spiking injections, also known as needle spiking, takes place when an unsuspecting person is injected with drugs using a needle.
Victims of needle spiking have reported discovering a painful pin-prick on their body after blacking out.
Lancashire police has recently updated its online guidance.
Temp Asst Chief Constable Russ Procter, said: “These reports are clearly very concerning and it is understandable people are worried and anxious.
“We take offences of this nature very seriously and all reports will be investigated thoroughly by our officers.
“We would encourage anyone who believes they have been a victim or witness to spiking, in any form, to contact us. Any reports of spiking will be investigated and taken seriously. You should try and report it to police as quickly as possible.