The general rule is six months after eruption of the first tooth. Taking your child to the dentist at a young age is the best way to prevent problems such as tooth decay, and can help parents learn how to clean their child's teeth and identify his or her fluoride needs.
Retching (also known as dry heaving) is the reverse movement (peristalsis) of the stomach and esophagus without vomiting. It can be caused by bad smell or choking, or by withdrawal from some medications after vomiting stops.
Retching involves a deep inspiration against a closed glottis. This, along with contraction of the abdomen, leads to a pressure difference between the abdominal and thoracic cavities. As a result, the stomach and gastric contents are displaced upwards toward the thoracic cavity.