Put on a pair of rubber gloves. Sweep the Drano crystals into a dust pan with a whisk broom and dispose of the crystals down the drain. Run water in the sink to neutralize the chemicals. Dip the whisk broom in a cup of vinegar or lemon juice. Pour the vinegar over the dust pan.
One of the biggest reasons people get bags under their eyes is because their parents have them. It's in your genes, and -- aside from plastic surgery -- there's not much that can be done about it. When you're young, lack of sleep, lack of exercise, a diet full of salty foods and water retention can also lead to bags.
Many people associate allergies with dark circles. This is a real and established connection. In fact, many doctors consider dark circles as an indication of allergies in children. Allergies cause dark circles in two ways: first, histamine reactions themselves can cause dark smudges to appear under the eyes. The biology of this is way too complicated to get into here.