The report from the medical examiner is in: Heath Ledger died from the “the combined effects of oxycodone, hydrocodone, diazepam, temazepam, alprazolam and doxylamine.” The brand names for the drugs that were in Ledger’s system are OxyContin, Valium, Xanax, Restoril, Unisom and Hydrocodone.

To be clear, Ledger didn’t die from an overdose of prescription drugs. He died from Adverse Drug Effects (ADEs) — a fatal reaction to the combination of medications he was taking.

As Dr. Kevin Pho of Kevin, M.D. surmises: “Two narcotics, three benzodiazepines, and one sedating antihistamine. If a single physician was responsible for these prescriptions, that’s a serious error in judgment. It is more likely that Mr. Ledger received multiple prescriptions from different physicians around the world, perhaps not knowing the danger these medications have when taken together.”

You might argue that no one in their right mind would take six different meds, even in prescribed doses, at the same time. But you’d be surprised how many Americans do. The majority of Baby Boomers, in fact, are on a regimen of four to six drugs.

In a world where pharmaceutical companies spend $60 billion annually on advertising and promotion, is it any wonder that we now believe there is a “pill for every ill” — and sometimes six?

Late last year, the FDA reported that ADEs, and deaths associated with them, have nearly tripled in the past decade. The FDA acknowledged at least 15,000 deaths are caused annually by drug effects, and conceded that many more go unreported.

How many more? The Journal of the American Medical Association has estimated that ADEs kill well over 100,000 people each year. Erick Von Schweber, founder of PharmaSURVEYOR, goes further — claiming ADEs are the third leading cause of death in the United States, responsible for more than 200,000 deaths each year. Of these, he says, at least 150,000 could be avoided if patients, their doctors and pharmacists were more careful in determining patient drug regimens.

“If you look at people’s drug regimens,” Von Schweber explains, “when they take not just one drug but multiple drugs, not only do they have interactions among drugs that can be harmful — can be fatal — but also there are risks involved in each individual drug. So even if the drugs are interaction-free, the risk is [compounded].”

“The barrier is complexity,” Von Schweber continues. “The typical senior, on a regimen of eight drugs, can have as many as 40 trillion alternate regimens to choose from that vary widely on ADEs … The patient, their family members and their physicians and pharmacists have had no means to navigate this … no decision support to identify the regimens that make the best trade-offs for the individual patient.”

Von Schweber’s PharmaSURVEYOR, which is in private beta with a launch planned later this year, promises a solution to this problem. Using Semantic Web technologies, the free-to-consumer Web application will take FDA data and combine it with information submitted by users, ensuring them that their drug regimens are safe — or warning them of their dangers. Here’s a sample profile a user might receive:

Until a solution like PharmaSURVEYOR is widely available, however, it is critical for patients to let their doctors know all of the drugs they are taking, as well as the dosages and quantities. Don’t be afraid to get a second opinion — and discuss your regimen with your pharmacist as well.

It seems clear that if Heath Ledger knew the combination of drugs he was taking might kill him, he never would have made such as tragic mistake. Let’s hope Ledger’s death can at least provide a lesson for others.