Free drug samples may pose serious risks to children, according to a study conducted by doctors from Cambridge Health Alliance and Hasbro Children's Hospital.

The study analyzed the findings of a survey carried out in 2004 by the Centers for Disease Control and Prevention, a survey which interrogated people on the method they received health care. Respondents were asked if they obtained free drug samples.

The authors, also researchers at Harvard Medical School and the Warren Alpert Medical School of Brown University, found that people who usually received those were children. More exactly, 1 out of 10 U.S. children obtained free drug samples from their physicians in 2004, the authors wrote in the journal Pediatrics.

Those who belonged to the lowest income group were found as likely as those in the highest income group to receive the free samples, mainly for the reason that poor individuals don’t commonly afford seeing doctors, the study showed.

However, this is not the biggest concern. Lead author Dr. Sarah Cutrona and colleagues said more attention should be paid to the type of drug samples doctors provide. Based on the 2004 survey, they said more than 500,000 children obtained free samples of four drugs that later carried safety warnings: Elidel, for eczema; Advair, for asthma; Adderall and Strattera for attention deficit disorder. Since the four medicines were new, their safety hadn’t been methodically examined and may put children’s health at risk.

“We need to discuss it more,” Dr. Cutrona said, “and maybe consider stopping the use of free samples entirely, if there are such potential harms.”