Lots of people are using complementary and alternative medicine (CAM) these days—things like vitamins, homeopathic or herbal medicine, chiropractors, acupuncture or massage therapy. But they don’t always tell their doctors about it.

In a study in the journal Pediatrics, researchers in Canada found that among kids with chronic health problems, 64.5 percent of them were using some form of CAM—but more than a third didn’t tell their doctor. That’s actually pretty good—other studies have shown that among the general population, as many as three-quarters of the people who use CAM don’t tell their doctors.

There are three reasons patients keep their mouths shut:

• They are afraid their doctor won’t be happy they are using CAM
• They don’t think the doctor needs to know
• The doctor didn’t ask

But it’s really important that patients talk to their doctors about any CAM they use.

First of all, we really need to know every medication a patient is taking, even if it’s only vitamins. Medications can have interactions, and some of them can be unexpected—I’ve certainly been surprised by some. Safety is always first and foremost, and we can’t know that we are being safe in our prescribing if we don’t know absolutely everything our patient is taking.

And while most vitamins, homeopathic remedies and herbs are safe, some can have dangerous side effects that people don’t realize. In the study, the most common way people learned about particular kinds of CAM was from family—and while we can always learn from the experience of others, it’s nice to have some input from someone with some clinical or scientific training (which not all family members have).

For similar reasons, it’s really important that we know everything a patient is doing, even if it’s just massage. Chances are we’re not going to discourage something like massage, but we want to be sure that we’re all working together, that the physical therapy or other regimens we’re prescribing work with what you are doing at home.

See, that’s the thing: medicine works best when the doctor and the family work as a team. It really helps to know not only what you are doing, but why. Did you use CAM because what we were doing wasn’t working? Then give us a chance to try something else. Did you use CAM out of curiosity or because you thought it might help? Then let’s think together about whether it’s the best approach—and whether there might be other things we should try instead or as well. Did you use CAM because it made your child better? Then definitely tell us, so that we can learn from it—and help other patients.

When I went to medical school, they didn’t teach us much about CAM. Granted, that was a long time ago, and things could be different now—but I’m guessing that for most medical schools, it’s not a big part of the curriculum. We doctors have a strong (and understandable) tendency to think within our own traditional medicine worlds.

But there is a much bigger world than traditional medicine when it comes to making patients feel and get better. And sometimes it’s patients who need to teach doctors.

I remember one mother who brought me a whole box of homeopathic medicines she used routinely to treat her children. I had never heard of most of them. I wrote down all the names and visited the website of the National Center for Complementary and Alternative Medicine (NCCAM) and read about each one—and learned a ton. Not only was I able to call the mother and talk about which ones might be helpful and which ones she should use with caution or avoid, but I gained a whole new understanding of homeopathy and herbs. Maybe I would have learned it all eventually, but it was that mother and her box of pills that got me to do it—and I will always be grateful.

Now, I can’t guarantee that every health care practitioner is going to be positive and want to spend time looking things up. But I think that more and more of us are open to different ways of treating things and want to learn more—and we just may need patients to help us learn. And we absolutely need to know everything that is going on with our patients in order to give them the best care, which is what is most important to us.

So don’t keep your mouth shut if you’ve tried an herbal remedy or been to the chiropractor or massage therapist. Even if we don’t ask, let us know. Let’s do things, and learn things, together.

Claire McCarthy is a primary care physician and the medical director of Boston Children’s Hospital’s Martha Eliot Health Center.  She blogs at Thriving, the Boston Children’s Hospital blog, Vector, the Boston Children’s Hospital science and clinical innovation blog, and MD Mama at Boston.com.