It's quite common in New Jersey and nationwide for doctors to prescribe medication to sick children that's not specifically designed or approved to handle their symptoms.

While off-label medications are legal, a new study out of Rutgers finds the practice is on the rise and research is lacking in determining whether many of these off-label drugs are doing more harm than good to the children ingesting them.

Using federal data from 2006 to 2015, the study found that nearly 20% of children's doctor office visits resulted in a doctor's order of one or more off-label drugs, often meant to treat common conditions such as respiratory infections, asthma or mental health disorders. Among visits with at least one ordered drug, the study found, the off-label rate increased from 42% in 2006 to 47% by 2015.

"Doctors might prescribe medicines off-label because there are no FDA-approved alternatives available, or because the approved options didn't work," said senior author Daniel Horton, assistant professor of pediatrics and a pediatric rheumatologist at Rutgers Robert Wood Johnson Medical School.

Use of some of these drugs is supported by high-quality scientific evidence, Horton noted. Drugs approved to prevent vomiting caused by chemotherapy, for example, also work to treat common causes of vomiting among children. Multiple clinical trials, meanwhile, support the off-label use of steroids for croup, an upper airway infection that generally occurs in children.

"Sometimes, though, off-label prescribing is done without adequate evidence that the drugs will work well or be safe," Horton said. "Our hope is that this kind of research describing patterns and trends of off-label use can help identify other medicines that are both off-label and lack enough evidence, so that research can work toward getting the necessary evidence."

According to the research, antihistamines and antibiotics for respiratory infections were the most frequently ordered off-label drugs over the 10-year period, as well as antidepressants for attention-deficit/hyperactivity disorder.

Specialists ordered off-label drugs more commonly than general practitioners, the study found. Rates were higher for female patients and for children with chronic conditions. The practice was used more often in southern states than other regions of the country.

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Contact reporter Dino Flammia at dino.flammia@townsquaremedia.com.