With more children using the products, the findings raise questions of the safety and validity of health claims which have followed the upsurge in herbal supplement usage.
The study also revealed that many parents are unaware of the potential side effects of common supplements and some do not even discuss their use with their child's paediatrician.
The report, conducted at Brenner Children's Hospital and published in the April issue of Paediatric Annals surveyed 145 families. According to the results, 45 per cent reported giving their child a herbal product with more than half of caregivers unsure whether herbal remedies interacted with other medications.
Only 45 per cent reported discussing their use with the child's primary health care provider.
The report states that "children with chronic, recurrent, and incurable conditions such as attention deficit/hyperactivity disorder (ADHD), asthma, skin rashes, allergies, cancer, inflammatory bowel disease, rheumatoid arthritis and cystic fibrosis have higher complementary and alternative medicine (CAM) and dietary supplement use rates than healthy populations."
Health care providers and parents face several challenges when recommending the use of herbs and dietary supplements with the potential side effects of common supplements on children of primary concern.
Kathi J. Kemper, a paediatrician at Brenner Children's Hospital said: "Children have their own unique physiology and metabolize, excrete and absorb supplements differently from adults. Even if a supplement has proven clinical efficacy and safety, the lack of standardization and regulation of supplements are obstacles in making recommendations."
"Efficacy, safety dosage and product recommendation should all be considered before recommending supplement use," Kemper advised.
Unlike drugs and pharmaceuticals, herbal products have not been scrutinized by the Food and Drug Administration. As well as the claimed beneficial effect some herbs and plants may have a toxic consequence.
"The bottom line is that parents should not equate 'natural' with safe," said Kemper.
"Parents should seek expert guidance when considering the use of CAM practices, and they should inform their child's paediatrician of any herb or dietary supplement their children take.
"It is critical that parents research what is known about the safe and effective use of a supplement when considering giving it to their children," Kemper recommended.
A report in the February issue of the American Journal of Respiratory and Critical Care Medicine (vol 169, pp 393-398) revealed that higher levels of the antioxidants beta-carotene and vitamin C, along with the antioxidant trace mineral selenium, were associated with a lower risk of asthma in a large study on young Americans.
The antioxidants had even stronger protection against asthma in subgroups of children exposed to passive smoke, said the researchers from Cornell University, New York.