Urea cycle disorders (UCDs ... One UCD, called ornithine transcarbamylase (OTC) deficiency, is what doctors call a sex-linked disorder. Mothers carry the gene on their X chromosome, and they ...

Your body naturally makes this hormone to control your sleep-wake cycle. A melatonin supplement ... you take it 20 minutes to 2 hours before bed. OTC sleep medication is most helpful for acute ...