[thomasz]

> There don't seem to be any long-term health risks.

As long as you don't count psychosis as health risk...

[treo]

Recent studies[1][2] have shown that psychosis only may be a risk if you already are prone to it.

[1] http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=S... [2] http://www.unboundmedicine.com/medline/ebm/record/16936704/a...