Mixed amphetamine salts: Difference between revisions
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Excellent bioavailability by all knows routes of administration, sources report ">75%" and "~90%". | |||
'''Distribution:''' | |||
The volume of distribution of amphetamine is 4 L/kg, and its plasma protein binding is less than 20%. | |||
'''Metabolism:''' | |||
Amphetamine is oxidized to form 4-hydroxyamphetamine, alpha-hydroxyamphetamine, or norephedrine. Both norephedrine and 4-hydroxyamphetamine are active metabolites and are further metabolized to form 4-hydroxy-norephedrine. | |||
The deamination of alpha-hydroxyamphetamine leads to the formation of phenylacetone, which is then metabolized to benzoic acid, its glucuronide conjugate, and hippuric acid, the glycine conjugate. | |||
'''CYP2D6''' is crucial in the metabolism of hydroxyamphetamine. Due to the genetic polymorphism of CYP2D6, variations in amphetamine metabolism may occur. Additionally, amphetamine inhibits monoamine oxidase (MAO), and both CYP1A2 and CYP3A4 contribute to its metabolism. [https://www.ncbi.nlm.nih.gov/sites/books/NBK507808/ cite] | |||
'''Elimination:''' | |||
Amphetamine is primarily excreted in the urine as metabolites, including alpha-hydroxy-amphetamine, with approximately 30% to 40% of the dose recovered as unchanged amphetamine. Due to its pKa of 9.9, the urinary elimination of amphetamine is influenced by urine pH and flow rates. An alkaline urine pH reduces ionization, which leads to decreased renal elimination. In contrast, acidic pH and increased urine flow rates enhance renal clearance, surpassing glomerular filtration rates (GFR), which suggests that active tubular secretion plays a significant role in excretion. The half-life of the D-enantiomer is 9 hours in children aged 6 to 12, whereas the L-enantiomer has a half-life of 11 hours. In adolescents aged 13 to 17, the D-enantiomer has a half-life of 11 hours, and the L-enantiomer ranges from 13 to 14 hours. In adults, the D-enantiomer has a half-life of 10 hours, whereas the L-enantiomer has a half-life of 13 hours.<h2 id="Pharmacodynamics">Pharmacodynamics</h2> | |||
REUPTAKE INHIBITION. EXCRETION!<h2 id="Indications">Indications</h2> | |||
Inattention, Fatigue<h2 id="Dosing">Dosing and titration</h2> | |||
Start Adderall XR 5 mg first thing in the morning. If insufficent, may take 10 mg the next day. Can increase 5 mg daily up to 30 mg or until effect.<h2 id="Effects">Effects</h2> | |||
so many<h2 id="Adverse">Adverse effects</h2> | |||
so few<h2 id="Contraindications">Contraindications</h2><span></span> | |||
few | |||
[[Category:Medicines]] | |||