A Cardiff University student died after taking ketamine and going into cardiac arrest, an inquest has heard.
Megan Pollitt, 18, died at the University Hospital of Wales in November 2020 with a fatal brain injury after taking the Class B drug and drinking heavily.
Megan's mother, Kelly Pollitt, described her daughter as "full of dreams and aspirations" with a "beautiful bright smile and positive energy".
Miss Pollitt, from Rugby in Warwickshire, had been at a party with friends at Talybont halls of residence the night she died, the inquest heard at Pontypridd Coroner's Court.
Emergency services were called to Talybont shortly after midnight on 14 November, following a report that Miss Pollitt had gone into cardiac arrest.
Miss Pollitt had no pulse when paramedics found her on the bathroom floor. They managed to resuscitate her and took her to University Hospital of Wales at 2am.
She suffered a severe brain injury due to swelling and died on 16 November.
Mrs Pollitt told the inquest that she last spoke to her daughter on 13 November - the day of the party.
"I spoke to her on FaceTime in the afternoon," she said.
"We talked through general things like where she was doing her food shopping, what she was having for dinner.
"She said she was having a house party that night or the following night. She seemed fit and healthy."
The inquest heard how Miss Pollitt had Type One diabetes, anxiety, and coeliac disease which involves an intolerance to gluten. She had also tested positive for Covid at the time of her death.
A toxicology report showed she had 169mg of alcohol per 100ml of blood. The legal limit for driving is 80mg.
Mrs Pollitt said: "We are taking it day by day but obviously it is hard.
"We are still trying to understand what happened in the week she moved into the new flat.
"It was suggested she hadn't been taking care of her diabetes well but I find this hard to understand. There are a lot of unanswered questions about what happened during that night."
PC Leighton Brown attended the flat in the early hours and spoke to her flatmates, who told the officer: "Basically she had some alcohol and she had something that was sold as ketamine. Obviously, we're not sure how pure the substance is.
"She was fine initially. She was just a bit ill."
Miss Pollitt's flatmates were interviewed by police, but no further action was taken.
Miss Pollitt had recently moved to a new room after "not feeling safe" in her original residences because of people taking drugs.
Mrs Pollitt told the inquest her daughter was "very anti-drugs" and drank "a normal amount for a student."
The assistant coroner recorded a conclusion of death by misadventure.
The cause of death was recorded as hypoxic-ischaemic encephalopathy following resuscitation from cardiac arrest as well as ketamine and alcohol toxicity in a female with Type One diabetes.
She found Miss Pollitt willingly consumed ketamine and alcohol before her death.
The head of Cardiff University's School of Law and Politics, Professor Urfan Khaliq, said at the time: "The loss to her family and friends is immeasurable. They are all in our thoughts and prayers. We are here to support them as we can."
Miss Pollitt's family added: "Meg dedicated her time to everyone around her and was always there for others.
"We will miss her beautiful bright smile and positive energy that would lift the spirits of anyone."