Use of heroin in pregnancy also may increase the risk of a variety of birth defects. What is not entirely clear is whether these effects are directly due to the drug itself or related to the poor health behaviors that women who take heroin often have. It may also be caused by the substances that the heroin often is mixed with when it is made. In more hopeful news, a recent survey of high school juniors and seniors found that 78% felt that heroin was "too great a risk" to try. The number of 12-17 year olds admitted to treatment for meth addiction more than doubled between 1994 and 2004. Withdrawal from methamphetamine can produce effects such as craving, exhaustion, depression, mental confusion, restlessness and insomnia, deep or disturbed sleep sometimes lasting up to 48 hours, extreme hunger, psychotic reaction, and anxiety reactions. | 
