Intranasal steroid medications for allergies may stunt growth in children, according to an Allegheny Health Network clinical trial published Monday.

The scientists preforming the clinical trial looked at 216 children ages 3 to 9 with allergic rhinitis (also known as hay fever). They found that those who used the steroid nasal spray had average growth of 5.65 centimeters (2.23 inches) over the 12-month study conducted at medical facilities nationwide, reported Post-Gazette. Those given the placebo nasal spray, on the other hand, has grew 6.09 centimeters (2.4 inches).

Previous studies have not linked child growth to steroid nasal allergy sprays, but the authors of this trial allege those clinical trials had design flaws that produced conflicting results. 

In Oct. 2013 the Food and Drug Administration (FDA) approved the drug Nasacort for over-the-counter use, which the study authors say exacerbates the risk of the spray because it can be given to misdiagnosed patients by their parents, reported Post-Gazette. 

"It should not be available for unregulated, unmonitored use," Dr. Skoner told Post-Gazette. "A parent picking this up and giving it to a child, first of all, might not have the right diagnosis and if the recommended dose doesn't have the desired result, the natural tendency in the U.S. is to double the dose. If you do that and it's not monitored by a physician there are going to be side effects of excessive steroid use."

Skoner testified in front of the FDA in 2013 in opposition to making the medication available over the counter. 

In the U.S. 6.6 million children were reported with hay fever last year, according to the Centers for Disease Control and Prevention. 

"[Steroids are] the most effective therapy for nasal allergies and for asthma as well, therein lies part of the problem," Skoner told Post-Gazette. "You may have a child treated with inhaled steroids for asthma and then you start giving them nasal steroids. There have not been a lot of studies done, but my prediction is the outcome is worse with two steroids." 

The study was published in the journal Pediatrics.