Claire Fielding, 34, would take up to four grams of the drug to "self-medicate" her condition that left her with a buzzing noise in her ears.
The mum-of-two's lips went blue and she struggled to breathe at her home in Bolton, Greater Manchester on the night of July 22.
Paramedics were called to the scene by her boyfriend of 17 years James Goodyear but Miss Fielding later died in Royal Bolton Hospital.
The Bolton inquest heard how the retail assistant died of a heat attack caused by taking cocaine that night or a large amount the weekend before.
"I knew that she took cocaine at weekends sometimes. It was a form of self medication for her."
Miss Fielding had been snorting cocaine since 2002, Dr Anindita Paul said.
Mr Goodyear described how she "wasn't in a good state" that night.
He added: "I had seen her like this before.
"Her lips had started to go blue. She wasn't in a good state."
The mum-of-two told the Bolton Drug and Alcohol Service she had reduced her cocaine intake to two grams and six units of alcohol a day – the equivalent of a half bottle of wine, an inquest heard.
She had been treated for her tinnitus and inflammation of the throat from February 3, 2016.
Assistant coroner Rachel Griffin said: "Claire has been described as a very bubbly and very caring young lady.
"She reported that she was using cocaine on a daily basis and that she was using the drug to a relatively high level.
"It is a very dangerous drug even in small amounts even with a one off use or long term use it can have fatal consequences."