The soul diva was found dead in her London home July 23. She had fought drug and alcohol problems for years.
Toxicology reports say there was alcohol in her bloodstream but it was unclear whether this contributed to her death.
The "Tears Dry on Their Own" singer was 27 years old.
Mitch Winehouse said Friday in a taping of Anderson Cooper's new syndicated talk show his daughter had been off drugs for two and a half years and was fighting alcohol problems, with occasional seizures.
He says her blood also contained traces of the prescription drug Librium, used to fight anxiety and withdrawal symptoms of alcoholism.