How do you deal with a hyperactive toddler? Is there any way to know if they are at risk for developing ADHD?

Developmentally, ADHD is not diagnosed till children are at least 6-7 years of age, although many are hyperactive before then. However, keep in mind that toddlers are expected to be very active anyway. Parenting strategies can be put in place to manage high activity levels, including having a structured routine for the day, ensuring sufficient sleep (ie. typically close to 12 hours of sleep for preschoolers), sufficient space to run around in to use up their energy (as many of our children are confined indoors for most of the day) etc. Many children who are sleep deprived appear 'high' even though they are very tired. They are trying to keep moving to keep themselves awake. Some parents notice their children being much more active after a sugar hit - this is a physiological reaction. It is usually easy to avoid high sugar items.