Intravenous administration route amphetamines

When indicated for therapeutic use, 5 to 60 mg or 5 to 20 mg of amphetamine or methamphetamine, respectively, are administered orally. An oral dose of amphetamine typically results in a peak plasma concentration of 110 ng/ml.2 When abused, amphetamines may be self-administered by the oral, intravenous, or smoked route. The last route of administration is common for methamphetamine. With heavy use, addicts may ingest up to 2000 mg per day. 

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