Emergency services were called to a home in Daisy Hill, Logan, about 25 kilometres from Brisbane, about 3pm on May 30, where a man and a woman were both found semi-conscious.
An 18-year-old man was taken to hospital where he was put in an induced coma for several days, before he died on June 4.
The woman was also put in an induced coma before she woke on June 1.
Police launched a homicide investigation and the woman, 40, was initially charged with attempted murder.
Her charge was later upgraded to murder.
Police say the woman and victim are known to each other.
The 40-year-old woman is due to appear at Beenleigh Magistrates Court today.
Anyone with information is urged to contact police or Crime Stoppers on 1800 333 000.
