It was a shot heard around the region this week when a teacher at Fine Elementary School in Attleboro was sent to Sturdy Memorial Hospital after mistakenly being administered an insulin injection by a school nurse during a flu clinic at the school. The teacher was reportedly "doing OK" and the school nurse involved was placed on paid administrative leave pending an investigation by school district and state officials.

Not much more can be drawn from this particular story as it now stands other than "mistakes happen." And they do. This may be small comfort. But it can serve as a reminder that patients - or their advocates - can sometimes help protect themselves.

Medical errors involving medicine, surgery, diagnosis, equipment and lab reports, may occur anywhere in the health care system from hospital to clinic, nursing home to pharmacy. They can happen for any variety of reasons, some beyond control of the patient. But some are not.

These are some general patient pro-active suggestions from the U.S. Department of Health & Human Services:

E At least once a year bring all your medicines and supplements with you to your doctor. "Brown bagging" your medicines can help you and your doctor talk about them and discover if there are problems. It can also help your doctor keep your records up to date. E Know what your doctor is prescribing and why, and when you pick up your medicine from the pharmacy, double-check: Is this the medicine that my doctor prescribed? A study by the Massachusetts College of Pharmacy and Allied Health Sciences found that 88 percent of medicine errors involved the wrong drug or the wrong dose.

E Speak up if you have questions or concerns. You have a right to question anyone who is involved with your care.

E When you are being discharged from the hospital, ask your doctor to explain the treatment plan you will use at home. This includes learning about your medicines and when you can get back to your regular activities. Research shows that at discharge time, some patients understand less than they should about what they should or should not do at home.

E Ask for information about your medicines in terms you can understand - both when your medicines are prescribed and when you receive them. What is the medicine for? How am I supposed to take it, and for how long? What side effects are likely? What do I do if they occur? Is this medicine safe to take with other medicines or dietary supplements I am taking? What food, drink, or activities should I avoid while taking this medicine?

The thorniness of medical errors is apparent in legislation pending in Massachusetts that would make an apology by a doctor inadmissible in court. Medical errors have gotten more attention, reports U.S. News & World Report this week, ever since the U.S. Institute of Medicine issued its 1999 report, "To Err is Human." It estimated that deaths of more than 100,000 Americans each year are tied to some form of medical mistake.

Mistakes do happen in every area of life. Heightened vigilance on everyone's part can help reduce their incidence.