A psychostimulant prodrug of the phenethylamine and amphetamine chemical classes.
Consists of dextroamphetamine coupled with the essential amino acid L-lysine.
Lisdexamfetamine, sold under the brand name Vyvanse among others.
A central nervous system (CNS) stimulant that works after being converted by the body into dextroamphetamine.
It is used to treat attention deficit hyperactivity disorder (ADHD) in people over the age of five as well as for moderate to severe binge eating disorder in adults.
Lisdexamfetamine is taken by mouth.
Pregnancy category US: C (Risk not ruled out)
US: Schedule II drug
Metabolism is by hydrolysis by enzymes in red blood cells initially.
Subsequent metabolism follows amphetamine pharmacokinetics.
Onset of action 2 h
Oral agent with a bioavailability of 96.4%.
Metabolism hepatic and primarily CYP2D6 after conversion to dextroamphetamine.
Half-life of less than 1 hour for the prodrug molecule, and 10-13 hours for dextroamphetamine.
Renal excretion about 2.%.
Available as 30mg Vyvanse capsules
Lisdexamfetamine is inactive and acts as a prodrug to dextroamphetamine.
Upon cleavage of the lysine portion of Lisdexamfetamine, dextroamphetamine is formed.
Prescribed for the treatment of attention deficit hyperactivity disorder (ADHD) in children six to twelve years and in adults.
Safety and the efficacy of the drug in people three to five years old have not been established.
Possibly efficacious for the treatment of major depressive disorder, cognitive impairment associated with schizophrenia, excessive daytime sleepiness, and binge eating disorder.
Utilized primarily as a treatment for attention deficit hyperactivity disorder (ADHD) and has similar off-label uses as those of other amphetamines.
Long-term treatment with amphetamine decreases abnormalities in brain structure and function found in subjects with ADHD, and improves function in several parts of the brain, such as the right caudate nucleus.
Psychostimulants are effective in treating ADHD because they increase neurotransmitter activity.
Use results in approximately 70% of improvements in ADHD symptoms
Therapeutic doses of this amphetamine improve cortical network efficiency.
Results in higher performance on working memory tests, motivation and increase arousal and goal-directed behavior.
Can improve performance on difficult and boring tasks.
Used by some students as a study aid, however, high doses can interfere with working memory and cognitive control.
Can increase stamina and alertness.
Increases physical strength, acceleration, stamina, and endurance, while reducing reaction time.
As an amphetamine increases stamina and endurance through reuptake inhibition and effluxion of dopamine in the central nervous system.
At elevated doses, can induce effects that severely impair performance, by rapid muscle breakdown and elevated body temperature.
Contraindicated in patients with hypersensitivity to amphetamine, in patients who have used a monoamine oxidase inhibitor (MAOI) within the last 14 days, in people with a history of drug abuse, heart disease, or severe agitation or anxiety, or in those currently experiencing arteriosclerosis, glaucoma, hyperthyroidism, or severe hypertension.
Classified in US pregnancy category C.
Amphetamine has also been shown to pass into breast milk.
Due to the potential for stunted growth the height and weight of children and adolescents on the drug should be monitored.
Cardiovascular side effects can include tachycardia, arrhythmias, hypertension or hypotension from a vasovagal response, and Raynaud’s phenomenon.
Sexual side effects may include erectile dysfunction, frequent erections, or prolonged erections in males.
Abdominal side effects may include abdominal pain, loss of appetite, nausea, and weight loss.
Other side effects include: dry mouth, grinding of the teeth, acne, sweating, blurred vision, reduced seizure threshold, and tics.
As an amphetamine it can stimulate the medullary respiratory centers and can produce faster and deeper breaths when respiration is already compromised, it may be evident.
As an amphetamine also induces contraction in the urinary bladder sphincter, which can result in difficulty urinating.
This drug therefore can be useful in treating bed wetting and loss of bladder control.
If intestinal activity is high, this amphetamine may reduce gastrointestinal motility or it may increase motility when the smooth muscle of the tract is relaxed.
Can enhance the pain relieving effects of opiates by its analgesic effect.
In children, young adults, and adults there is no association of amphetamines with serious adverse cardiovascular events such as sudden death, heart attack, and stroke.
Effects of therapeutic doses can include increased alertness, apprehension, and increased concentration.
An amphetamine overdose may induce brisk reflexes, confusion, high or low blood pressure, hyperthermia, inability to urinate, involuntary muscle twitching, irregular heartbeat, muscle pain, painful urination, rapid breathing, and severe agitation.
Overdose may produce symptoms such as psychosis, brain hemorrhage, cardiogenic shock, circulatory collapse, compulsive and repetitive behavior, hypokalemia, or hyperkalemia, fever, pulmonary edema, pulmonary hypertension, kidney failure, metabolic acidosis, renal failure, muscle breakdown, respiratory alkalosis, serotonin syndrome and sympathetic syndrome, convulsions, coma and death.
Addiction is a risk with recreational amphetamine, but is unlikely to arise from medical use at therapeutic doses.
Tolerance develops rapidly in amphetamine abuse, so larger doses are required to achieve the same effect.
There is currently no effective pharmacological treatment for amphetamine addiction or abuse.
Abuse of amphetamine can result in psychoses that may present with paranoia, hallucinations, and delusions, and that 5-15% of users fail to recover completely.
Psychosis very rarely arises from therapeutic use of amphetamines.
High-dose can cause indirect neurotoxicity as a result of increased oxidative stress from reactive oxygen species and autoxidation of dopamine.
Withdrawal symptoms in chronic, high-dose amphetamine users are frequent, occurring in up to 87.6% of cases, and persist for 3-4 weeks with a marked acute phase occurring during the first week.
Amphetamine withdrawal symptoms include: anxiety, drug craving, depression, fatigue, increased appetite, increased or decreased movement, lack of motivation, sleeplessness or sleepiness, and lucid dreams.
Withdrawal symptoms are associated with the degree of dependence, suggesting that therapeutic use would result in far milder discontinuation symptoms.
Drugs that acidify the urine, such as ascorbic acid, increase urinary excretion of amphetamines, decreasing the drug’s half-life time.
Drugs that alkalinize the urine, such as sodium bicarbonate, decrease urinary excretion thus increasing the half-life time.
Concomitant use of MAOIs can cause hypertensive crisis.
As an amphetamine it enters the presynaptic neuron across the neuronal membrane or through DAT.
It is an inactive prodrug that is converted in the body to dextroamphetamine, a pharmacologically active compound which is responsible for the drug’s activity.
After oral ingestion, it is broken down by enzymes in red blood cells to form L-lysine, a naturally occurring essential amino acid, and dextroamphetamine.
A single-enantiomer dextroamphetamine formula.
May have less abuse potential than dextroamphetamine and an abuse profile similar to diethylpropion at dosages approved for treatment of ADHD.
Has a high abuse potential when this dosage is exceeded by over 100%.
Dosages of 30, 50 or 70 mg/day of oral lisdexamfetamine has a significantly greater improvement in ADHD-Rating Scale total score than placebo.
Not an effective treatment for depression.
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