Comparative Pharmacology
Head-to-head clinical analysis: AMPHETAMINE SULFATE versus METHAMPEX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AMPHETAMINE SULFATE versus METHAMPEX.
AMPHETAMINE SULFATE vs METHAMPEX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Increases presynaptic release of dopamine and norepinephrine, blocks reuptake, and inhibits monoamine oxidase, resulting in CNS stimulation.
Methamphetamine is a sympathomimetic amine that increases synaptic concentrations of dopamine, norepinephrine, and serotonin by promoting their release from presynaptic terminals and inhibiting their reuptake. It also inhibits monoamine oxidase, reducing neurotransmitter catabolism.
5–60 mg/day orally in 1–3 divided doses, initial 5 mg once or twice daily, increase by 5 mg weekly.
150 mg orally twice daily for 12 weeks; alternative: 90 mg orally twice daily if tolerability issues.
None Documented
None Documented
Terminal elimination half-life: 10-13 hours in adults with acidic urine; prolonged to 16-34 hours with alkaline urine. In children, half-life is typically shorter (6-8 hours).
Terminal elimination half-life is approximately 9-14 hours in adults with normal renal function (mean ~12 hours). In children, half-life is shorter (~8-10 hours). Context: Steady-state is achieved within 2-3 days. Half-life may be prolonged in patients with renal impairment (up to 20-30 hours) or alkaline urine (up to 30 hours).
Renal excretion of unchanged amphetamine (approximately 30-40%) and its metabolites; urinary pH-dependent: acidic urine enhances elimination (up to 70% unchanged), alkaline urine reduces it. Minor biliary/fecal elimination (<10%).
Primarily renal excretion (≥90% as unchanged drug and metabolites); approximately 70-80% as unchanged amphetamine, 10-15% as deaminated metabolites (hippuric acid, benzoic acid). Biliary/fecal excretion is negligible (<5%). Renal clearance is pH-dependent; acidic urine increases elimination. In overdose or renal impairment, elimination half-life may prolong.
Category D/X
Category C
CNS Stimulant
CNS Stimulant