This patient's weight loss, sleep disturbance, mood changes, paranoia, and physical findings of poor dentition and skin excoriations and sores are consistent with chronic methamphetamine use. Methamphetamine (also known as "meth," "crystal meth," "ice," and "glass") is a highly addictive and very potent central nervous stimulant that can cause marked weight loss and behavioral changes. Psychotic symptoms (eg, paranoia, persecutory delusions, visual and tactile hallucinations), as described in this patient's recent hospitalization, can occur. Physical findings may include lesions due to chronic skin picking performed in response to tactile hallucinations of bugs crawling under the skin (formication). Severe dental problems ("meth mouth") include tooth decay, brown discoloration, and cracked teeth due to severe clenching.
Methamphetamine use disorder typically involves repeated periods of intense use, intermittent sobriety, and relapse. Features of acute intoxication include increased energy and euphoria, agitation, and signs of sympathetic overactivity (eg, elevated pulse and blood pressure, hyperthermia, sweating, pupillary dilation). Some patients with chronic methamphetamine use disorder can develop persistent psychosis that may be difficult to distinguish from primary psychotic disorders. Visual and tactile hallucinations tend to be more common than auditory hallucinations in methamphetamine use disorder.