TROY, Mich. -- A Troy family is suing Rite Aid over a pharmacy error.

John Sheridan, 54, was prescribed Temodar as part of a cancer treatment regimen.

Sheridan was supposed to take 360 milligrams a day for 7 days a week, every other week.

The order was written 250 milligrams -- 14 times a day for 7 days -- nearly 10 times the correct dosage.

The Rite Aid store in Troy dispensed the prescription to Sheridan back in 2007.

Two days after he began taking the medication, he was taken to the emergency room.

Less than a month later, he died. Sheridan's attorney Brian McKeen said the lethal dosage of the drug that was supposed to help him fight cancer wiped out his immune system.

"You just want to put your faith in your doctor and the pharmacy and to do right by you and your loved one, and that just didn't happen for us," said John Sheridan's wife Katherine.

Sheridan's oncologist settled with the family before legal action took place.

Although the oncologist wrote the prescription, McKeen said, "Rite Aid's responsibility is to ensure that proper policies and procedures are adopted and followed to make it impossible for a mistake of this proportion to occur. Their pharmacists should have recognized the documented fatal dosage of the drug Temodar is 2000 milligrams daily, and proactively contacted the prescribing physician to clarify the dangerously high dosage level."

Katherine Sheridan said that event though her husband's cancer was terminal when he was prescribed the wrong dose, his quality of life was still good and he was even working.

"It has always been extremely painful for my girls and I to think that this happened to him. ... We would have enjoyed every additional day we got with him," said John Sheridan's wife Katherine.