Amphetamines: Central & peripheral sympathomimetic effects that can lead to life-threatening complications. Repeated use can cause neuropsychiatric sequelae. Incl. Metamphetamine (crystal meth or ice), methylphenidate (Ritalin), 3,4-Methylenedioxymethamphetamine (MDMA,Ecstasy).
Cocaine: Sympathomimetic and local anaesthetic effects that can lead to lethal complications
Amphetamines: Enhance catecholamine release and block their re-uptake and inhibit MAO. NA, D & 5HT stimulation results. MDMA may induce SIADH.
Cocaine: Blocks catecholamine re-uptake, causes vasospasm and blocks fast Na channels.
Amphetamines: Well abs orally or insufflation. Large Vd (lipophilic weak bases)
Cocaine: Well abs through mucosal membranes of URT & LRT & GIT.Bioavail dependent on route. Moderate Vd (lipid soluble). Rapidly metab by liver & plasma cholinesterases. T½30–90min.
May present with acute intoxication, complications of abuse or psychiatric sequelae. Acutely: