The family of an Ohio killer put to death with a controversial, unused drug plans to file a lawsuit against the Ohio Department of Rehabiliation and Corrections, NBC News reported.

"I can't think of any other way to describe it than torture," said Amber McGuire, daughter of Dennis McGuire, who was executed on Thursday after being administered a combination of drugs that have never been used before.

After being given the drugs, McGuire, 53, reportedly made loud snorting noises for 25 minutes before being pronounced dead at 10:53 a.m. It was the longest capital punishment procedure in the state since Ohio resumed the punishment in 1999.

McGuire received the death sentence for raping and killing Joy Stewart, a 22-year-old pregnant newlywed, in 1989.

Jon Paul Rion, an attorney for McGuire's family, said they plan to sue "to make sure that this procedure is not utlized on anyone else ever."

Prior to the execution, defense attorneys pleaded for the court to delay his death in fear of the unused drug causing "air hunger," inflicting "terror and agony" upon McGuire.

However, the prosecution argued that "you're not entitled to a pain-free execution." The court agreed with the prosecution, though admitted that the use of the new drug would be an "experiment."

Rion claims McGuire's death violated the Eighth Amendment because "the facts would demonstrate that it was cruel and very unusual," adding his son and daughter "watched their father gasping for over 19 minutes."

He added that McGuire "spoke to his son and made his son promise that if things don't go right -- because everyone feared that it wouldn't -- he would pursue this to make sure that it wouldn't happen to anyone else."

Rion said the family is not interested in winning money.

Though officials from the Ohio Department of Rehabiliation and Corrections have not commented, a spokeswoman for the prisons said a review of the case will be conducted, as it is for every execution case.