A managed care company is expanding a program that tries to prevent accidental drug overdoses.

Aetna Inc., Hartford, says it will be applying its therapeutic duplication program to selective serotonin reuptake inhibitors, which treat depression; proton pump inhibitors, which treat ulcers; and triptan drugs, which treat migraine headaches.

Aetna began testing the program on statin prescriptions in January 2007.

Statins help patients reduce blood cholesterol levels.

Excessive use of the drugs can cause liver problems and kidney failure, but, in some cases, 2 different doctors issue statin prescriptions to the same patient, without realizing that the patients will be getting a double dose of statins, Aetna says.

Aetna fought statin duplication by working with the pharmacies in its network to look for signs of statin prescription duplication.

The program found about 4,800 incidents of possible therapeutic duplication, and it led to pharmacists not filling 3,500 duplicate prescriptions, Aetna says.