An estimated 20 percent of Americans have abused prescription drugs, according to a 2008 government survey. And even without abuse, prescription drugs, if mixed the wrong way or taken under the wrong conditions, can be deadly.
Here are seven tragic celebrity stories of abuse, accidental deaths and outright suicide.
Greg Giraldo 2010Lawyers are usually the butt of jokes, but Greg Giraldo ditched a legal career to be the comedian telling them.
He became a Comedy Central favorite for his dry wit and sharp tongue.
But on Sept. 29, 2010, the curtain came down on Giraldo. He died from a prescription drug overdose, although it was not immediately clear which ones.
He was only 44.
Brittany Murphy 2009On Dec. 20, 2009 actress Brittany Murphy died in her Los Angeles home of a heart attack. But that wasn't the whole story for the 32-year-old.
A coroner's report blamed pneumonia, iron deficiency and "multiple drug intoxication."
A combination of prescription vicoprofen (a narcotic pain reliever) and over-the-counter cold medications were found in her blood, her husband Simon Monjack said.
Five months later, he was found dead in the same home.
The cause was acute pneumonia and severe anemia, according to the coroner. Prescription drugs were not thought to be a factor.
Heath Ledger 2008Oscar-winning actor Heath Ledger was found unconscious in his New York apartment on Jan. 22, 2008 at age 28.
The medical examiner's office said he died of an accidental overdose of painkillers, sleeping pills, anti-anxiety medication and other prescription drugs.
Anna Nicole Smith 2007Former Playboy playmate and reality star Anna Nicole Smith died after being found unconscious in a Florida hotel room on Feb. 8, 2007.
She was 39.
She died of "combined drug intoxication" with the sleeping medication chloral hydrate as the major factor, according to the Associated Press.
Smith was taking a lengthy list of other medications, including methadone for pain.
Rob Pilatus 1998German-born Rob Pilatus (right) of the doomed 90's pop duo Milli Vanilli was found dead of a suspected alcohol and prescription pill overdose in a Frankfurt hotel room on April 2, 1998.
He and Fabrice Morvan, Milli Vanilli's other half, were suspected of - and eventually confessed - to having lip-synced most of their recordings.
Pilatus' death was ruled accidental, but he had previously tried to kill himself, according to the New York Times.
Keith Moon 1978The drummer for the iconic band The Who, shown here on right, was known for erratic behavior and problems with addiction. Nevertheless, when he died in 1978 due to an overdose of a powerful sedative that had been prescribed for alcohol withdrawal, his death was ruled accidental.
But as with many such deaths where the victim is on prescribed medication and also abuses other drugs, the direct cause of death can be a prolonged matter of debate.
Judy Garland 1969Judy Garland, who will never be forgotten for her starring role in "The Wizard of Oz," was found dead at age 47 on June 22, 1969. The coroner stated that the cause of death was "an incautious self-overdosage" of barbiturates, according to one of her biographers, Gerald Clarke.
Her death certificate states that it was accidental. However, there is speculation that it was suicide.
Dorothy Dandridge 1965Best known for her starring role in the 1955 hit "Carmen Jones," heart-stoppingly beautiful African-American actress Dorothy Dandridge died in September 1965 at age 42 due to an overdose of the antidepressant Imipramine, according to a profile in the Washington Post.
Whether her death was an accident or suicide remains an open question.
Marilyn Monroe 1962Marilyn Monroe was found dead on Aug. 5, 1962. She was 36. The Los Angeles County Coroners office recorded cause of death as "acute barbiturate poisoning," resulting from a "probable suicide."
Photos: Marilyn Monroe
Video: "48 Hours" on Marilyn Monroe