The country’s major drug store chains are increasingly relying on pharmacy technicians, often as young as 16 with little training, to fill prescriptions involving even the most powerful drugs. Sometimes, there are tragic results. A high school-aged pharmacy technician at a Walgreens in Lakeland, Fla., made a typing error and dispensed a dose of the blood thinner Coumadin that was 10 times what the doctor had prescribed. THE BLOTTER RECOMMENDS Photos Unreported Pharmacy Errors Blotter U.S. Pharmacy Errors: Unreported Epidemic? Good Morning America Video What Your Pharmacist Doesn’t Tell You Click Here for Brian Ross Slideshows. "She was in high school. Her prior job had been cleaning a movie theater and serving popcorn," said Karen Terry, a lawyer representing the patient’s family. The patient, Beth Hippely, suffered a massive stroke after taking the medicine she was incorrectly given, forcing her to stop chemotherapy for a treatable, stage II breast cancer. She died earlier this year. See Unreported Pharmacy Errors in Pictures. Under Walgreens policy, prescriptions filled by pharmacy technicians are supposed to be double-checked by registered pharmacists. In the Hippely case, the registered pharmacist failed to catch the high school student’s error. As big chain drug stores have rapidly expanded, thousands of pharmacy technicians have been hired. "We depend on them very heavily in our industry," said Mary Ann Wagner, senior vice president of the National Association of Drug Store Chains. Click Here for Full Blotter Coverage. In a majority of states all that is required is that the student be actively working for a GED or high school diploma. The amount of training varies from store to store, with some chains requiring only that the students watch a short video before taking the job. "They’re giving a huge responsibility to people that aren’t trained to perform those duties," says Karen Terry. The high school student who made the error with Beth Hippely testified she had watched a video and was taking classes in school to learn about the pharmacy job. Testimony in the Hippely case also revealed that stock boys and photo shop workers were also pressed into service behind the pharmacy counter when the store became very busy. "They know mis-fills and errors are bound to occur because they’re giving huge responsibility and important responsibility to people that aren’t trained to perform those duties," said Terry. "This is an intentional, system drive for profits, for money. If it wasn’t about that, they would hire more pharmacists," the lawyer said. Walgreens is the country’s biggest pharmacy and recently reported record profits. In a statement to ABCNews.com, Walgreens said, "We deeply regret the few errors that have occurred among the more than 500 million prescriptions we fill each year at our 5,600 pharmacies.