Whitney Houston's medical, pharmacy records subpoenaed

(CBS/AP) As the Whitney Houston investigation continues,  the Los Angeles County coroner's office has issued subpoenas for medical and pharmacy records from Whitney Houston's doctors and medical providers.

This is standard procedure in such investigations, an official said.

Assistant Chief Coroner Ed Winter said the request is made in virtually all death investigations because it can shed additional light on how people died and whether they had any serious medical conditions.

"We've already contacted a number of doctors with requests for records," he said. Winter said that requests for medical records are requested through subpoenas.

"If somebody even dies in a crash, a blunt force trauma, we will still take medical issues into account," he said. "Anything helps."

Investigators in the Houston case said they found several bottles of prescription medication in the Beverly Hills, Calif., hotel room where she died Saturday, although Winter has said they weren't an unusually large number. Detectives have declined to disclose which medications were seized.

Authorities said an autopsy found no indications of foul play or obvious signs of trauma. It could be weeks before the coroner's office completes toxicology tests to establish the cause of death.

Medical records have become crucial in celebrity death investigations, including inquiries into what killed actor Corey Haim, actress Brittany Murphy and pop superstar Michael Jackson.

Haim's death was caused by pneumonia and was not drug-related, the coroner's office ruled. Prescription medications were cited as a contributing factor in Murphy's death, which the  coroner determined was caused by pneumonia and severe anemia. Murphy, who was ill in the days before she died in December 2009, showed no signs of drug abuse, a coroner's report stated.

Houston died just hours before she was scheduled to appear at producer Clive Davis' pre-Grammy Awards bash.

Her family plans to hold a private church service Saturday in her hometown of Newark, N.J.