Amphetamine-like drugs are used as pills or capsules, powder, or fluid, and can be ingested orally, smoked, insufflated, or injected intravenously. They cause euphoria but tolerance develops rapidly. Clinically evident effects of the two drugs are nearly indistinguishable, but methamphetamine appears to be a more potent stimulant. Amphetamine and methamphetamine induce euphoria, increased energy, alertness and libido, agitation and anxiety, increased locomotor activity and stereotypical movements, as well as hyperthermia, increased heart rate and blood pressure, vasoconstriction, bronchodilatation, hyperglycemia, and suppress appetite. Psychosis, hyperkinesia, seizures, and coma have been described in emergency patients. Chronic users may develop behavioral disorders, impulsivity, punding (non-goal directed repetitive activities), hallucinations, tremor, choreoathetosis, dystonias, ataxia, and gait disturbances (41–43). Stereotyped involuntary choreoathetotic hyperkinesias are characteristic in arms, neck and head, and usually disappear during sleep, while teeth grinding (bruxism) may occur during day and night. Movement disorders may develop during abuse or abstinence, and though they a usually resolve within few days, they may remain for a long time in some cases, even after the abuse of amphetamines is stopped. Treatment with benzodiazepines or neuroleptics may be of benefit (43–45). Choreiform movements have developed as an adverse effect in the therapeutic setting of amphetamine used in the treatment of ADHD in adult and pediatric patients (46, 47).
[41] https://www.ncbi.nlm.nih.gov/pubmed/23688691/
[43] https://www.ncbi.nlm.nih.gov/pubmed/3355623/
[45] https://www.ncbi.nlm.nih.gov/pubmed/7299411/
[46] https://www.ncbi.nlm.nih.gov/pubmed/22883290/
[47] https://www.ncbi.nlm.nih.gov/pubmed/15254949/