Ritalin Used in Treating ADHD in Kids May Cause Heart Risks

A popular drug for treating attention-deficit hyperactivity disorder (ADHD) in children has been linked to increased risk of abnormal heart rhythm, researchers warn.

Methylphenidate, a central nervous system stimulant used in treating ADHD, is said to increase the risk of arrhythmias or abnormal heart rhythm during the first two months of use of children and teens.

Methylphenidate is sold under popular brand names Ritalin, Daytrana and Concerta.

A team of researchers from Australia, Canada and South Korea conducted a study among 100,000 children and young people with ADHD, measuring the cardiac safety of methylphenidate.

The study, which was published by The BMJ, examined 1,224 patients in South Korea National Health Insurance Database aged 17 and below who had experienced an "incident cardiovascular event."

This was comprised of 864 patients with arrhythmias, 396 with hypertension, 52 with myocardial infarctions, 67 with stroke and 44 with heart failure.

The researchers found out that methylphenidate increased the risk of arrhythmia by 61 percent during the first two months of use, compared with periods of non-use of the drug.

The risk was even higher in the first three days of use.

However, researchers said that the findings of the study should not cause panic. According to Nicole Pratt, senior study author and a senior research fellow at the Quality Use of Medicines and Pharmacy Research Center at the University of South Australia, most children on methylphenidate should not experience heart problems.

"In the average child, the risk of serious cardiovascular events is extremely small (three per 100,000 per year), and any absolute excess risk associated with methylphenidate is also likely to be small," Pratt said in a report published in WebMD.

Also, the study holds no proof that the drug causes irregular heartbeat.

But according to Pratt, doctors should still take these findings into account when prescribing methylphenidate to a child.

The study found that children with existing congenital heart disease are said to be the most affected.

The researchers found no significant increased risk of heart attack in these kids, and no increased risk of high blood pressure, stroke or heart failure.

Although risk is relatively low, the researchers suggest that the medication benefits should still be carefully considered.

"With the increased use of drugs for ADHD globally, the benefits of methylphenidate should be carefully weighed against the potential cardiovascular risks of these drugs in children and adolescents," researchers said.