Low-dose ADHD medications do not affect thyroid function, growth hormone at 1 year
Disclosures: The authors report no relevant financial information.
According to study data, in children diagnosed with ADHD, low doses of ADHD medications did not affect thyroid or growth hormone levels.
Trends in hormone indices of children with ADHD who received long-term drug treatment remain controversial, according to Liang-Jen Wang, MD, MPH, PhD, visiting staff member of the Department of Child and Adolescent Psychiatry at Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine in Kaohsiung, Taiwan, and colleagues. The researchers conducted the prospective study to determine any changes in the GH and thyroid hormone systems in children with ADHD receiving various drug treatments.
The study included 118 children diagnosed with ADHD who were drug naïve and observed naturalistically for 12 months. Of the participants, 22 received no medication, while 39 were treated with low-dose short-acting methylphenidate (MPH; 14 ± 6.7 mg/day), 40 with an oral release system long-acting osmotic (OROS) (32 ± 9.6 mg/day) and 17 with atomoxetine (29.2 ± 9.7 mg/day). The groups were similar in terms of age, gender distribution, height, weight, and severity of ADHD symptoms, among other variables.
The researchers took blood samples at baseline and at 12 months to measure serum levels of insulin-like growth factor I, IGF-binding protein 3 (IGFBP-3), prolactin, thyroid, triiodothyronine, thyroxine and free T.4.
All four groups had comparable trends for IGF-I, IGFBP-3, prolactin, TSH, T3T4 and free T4 levels. The researchers noted that changes in serum IGF-I levels were positively correlated with height changes (P P
“Trends in GH and thyroid function were similar in ADHD children without drug treatment and in patients who received various drug treatments (immediate-release MPH, OROS-MPH or atomoxetine) during the 12-month observation “, concluded the researchers. “The results of this study provide new information for clinicians, as low doses of ADHD medications showed no adverse effects on children’s growth and hormonal systems over a 12-month period. Nevertheless, patient growth and appropriateness of drug dosage should be closely monitored in ADHD patients with long-term pharmacotherapy.