order. However, it has not been determined that these substances produce a substance use
disorder. Despite tolerance, these gases may no t alter behavior through central effects, and
they may be used only for their peripheral effects.
Substance use disorders generall y are associated with elevated risks of suicide, but there
is no evidence of unique risk factors for suicide with other (or unknown) substance use
disorder.
Prevalence
Based on extremely limited data, the prevalence of other (or unknown) substance use disorder