I'm not sure what she's on, if it were meth she would have very bad teeth.
http://www.npr.org/templates/story/story.php?storyId=4793417
Meth is made from hydrochloric acid. When users smoke meth, the acid in the drug erodes their tooth enamel. The drug also leaves users dehydrated and craving sweets. Add up a loss of tooth enamel, a constant sweet tooth and a disregard for brushing, and you end up with teeth that are little more than little black stubs -- a condition known as "meth mouth."