The request arrived by e-mail, from a mother on behalf of her teenage son. “He is still having foot pain, and we need an excuse for phys ed. Can you write a note?”

A few weeks earlier, I had seen the boy, a competitive athlete, and diagnosed Sever’s apophysitis, an inflammation of the heel bone, a common problem that is a lot less serious than it sounds. I reassured her that with rest, pain medication and time, it would get better.

I wrote a note excusing the boy from physical activity for two weeks, since intensive running and jumping would aggravate the condition.

This was a sincere kid in a family I had a good relationship with, so when I got that second request for a PE excuse note, stating the same pattern and location of pain, I complied, reiterating my original medical advice.

Less than two weeks after that, I received another message from the boy’s mother: “He’s still in pain, and it got worse after [sports] tryouts. Can he stay out of PE longer?”

“After tryouts?” I wrote back, with a growing sense that I had been taken for a ride. “Just so I understand, you let him try out for a team, even though I had excused him from PE, and now you want another note from me?” She confirmed that her son had tried out for a sports team while having stayed out of PE because of my note.

Like many doctors, I am increasingly besieged by requests for excuse notes. The majority of these notes are for infectious illness and aches and pains that require a student to get a respite. Many of the requests are legitimate. Keeping a sick kid out of school or an injured kid off the field is a good thing.

But school notes are becoming the bane of a pediatrician’s existence. They put a burden on our practice and often put doctors in the odd position of arbiters between students and schools, giving us an uncomfortable power. I can excuse a kid from PE, a game, a day of school — in fact, from months of class, or even longer. Whatever we write is assumed true and clinically accurate. But as the case involving the tryouts demonstrates, we’re not always given the full story.

Often the requests come without having the patient come into the office. The reasons are many. For example, the child is better and needs a note after the fact:“My child was sick last week; he’s better now, so can I get a note to cover his illness?” In other situations, the parents are too busy, can’t take a day off from work or don’t want to pay for a visit. Schools and child-care centers often demand a note to make sure a child doesn’t have — or has been treated for — a contagious illness such as pinkeye before being allowed back in.

Other requests require visits that are largely unnecessary. In some states, schools are under the pressure of having their funding tied to attendance rates. Regardless, schools want to keep kids in school. Doing so sometimes means asking that a student get a clearance note from a doctor for a minor ailment that otherwise wouldn’t require an office visit.

While that may make sense for the school, an appointment triggered only by a school’s attendance rule puts a burden on a parent. It also may make it impossible for a kid who really needs to see his doctor to do so. What then? Maybe that child ends up being seen where the doctor or provider may not know him well, such as at an urgent care center or emergency room. Parents also lose in having to get children to the doctor for things that in a different time did not require any sort of medical opinion.

Also, in some cases parents and kids take advantage of the physician’s excuse. If it’s not to help a child save herself from PE so she can be ready for track tryouts, say, it’s to get other breaks.

Once I had a family request a note intended to have a child assigned to attend a particular high school. Their rationale? The child had a mild case of scoliosis (curvature of the spine) and so “he needed” to be at the school closer (and more highly rated) than the one he was slated to attend. I declined their request. Given that most cases of scoliosis are completely without any symptoms or impact on a person’s health, I’m quite sure any colleague or spine specialist would have done the same.

So how can we fix this problem? I’ve borrowed an idea from the British — “fit notes,” which focus on what a patient can do rather than what he or she can’t. In these missives, I would, for example, excuse a student from basketball because of heel pain but tell the PE teacher the student can exercise on a stationary bike or do some upper-body weightlifting or other activity that’s non-weight-bearing. So far I haven’t gotten any pushback.

With respect to infections, I would suggest that schools be mindful of the latest recommendations from doctors, with an eye toward both keeping infections at bay and keeping kids in school. For example, too many schools still bar kids with treated head lice because they see a few nits (lice eggs) in a child’s hair, even though those bugs are most likely dead. The American Academy of Pediatrics a few years ago suggested that schools move away from a “no nit” policy. Still, nearly four years after that policy was adopted, I regularly receive requests from parents whose kids have been referred for “clearance” to attend school after the child has been treated for lice at home with over-the-counter medicine.

Moving forward, school systems, doctors and parents need to agree on guidelines that help keep kids in school or get them back as soon as possible and that spell out when a doctor’s note might be needed for the good of others.

As for my patient with the sore foot, I turned down his mother’s persistent request for another note. She had taken advantage of my trust, and I told her the issue was between her and the school to figure out. Her message back suggested she had gotten the point. I have had no such further requests from her. We both learned a lesson.

Parikh is a pediatrician in Walnut Creek, Calif.