Adderall is a brand-name pharmaceutical psychostimulant composed of mixed amphetamine salts, the actions of which are sympathomimetic. The drug is used primarily to treat attention-deficit hyperactivity disorder and narcolepsy, which are its only two approved indications for use in the United States. It is available in two formulations: immediate release and extended release (XR). The XR formulation, however, is not approved to treat narcolepsy.[1]
Adderall has also been used successfully to manage severe cases of treatment-resistant depression. Individuals who show little or no response to typical antidepressants, including SSRIs and tricyclic antidepressants, are more likely to respond to psychostimulant therapy. These patients, however, are the exception, rather than the norm among those with depression and this is not an approved indication. Other recognized uses include[2]:
These above uses are not necessarily licensed in any particular country; for example they are not FDA approved in the USA.
Shire Pharmaceuticals introduced the Adderall brand in 1996 in the form of a multi-dose, instant-release tablet derived from an original formula of the weight management drug Obetrol. In 2006, Shire agreed to sell rights to the Adderall name for this instant-release medication to Duramed Pharmaceuticals[3] and this instant-release medication has since become available in a generic formulation of "mixed amphetamine salts"[4]. The active ingredients of Adderall include a combination of dextroamphetamine and racemic DL-amphetamine salts.[4] In 2001, Shire Pharmaceuticals introduced an extended-release preparation of these ingredients in a variety of dosages under the brand name "Adderall XR" (extended release), on which Shire retains exclusive patent rights until the patent expires, expected in 2009.[5]
Specifically, Adderall XR is composed of the following proportions of active ingredients[6]:
These four salts are metabolized at different rates and possess diverse half lives, therefore resulting in a less dramatic onset and termination of therapeutic action; as compared to single-salt amphetamine preparations.[4]
The average elimination half-life in adults for dextroamphetamine and levoamphetamine is 10 hours and 13 hours respectively. Breakdown rates are affected by many factors including urinary and stomach pH, weight, gender, other medications being taken, and age. Alkaline increases bioavailability and acidic foods cause the drug to be excreted sooner.
Urinary and stomach pH levels can have the strongest effect on DL-amphetamine excretion and absorption. Co-administration of acidic substances (e.g. citric acid) causes an accelerated excretion of DL-amphetamine while co-administration of alkaline agents (e.g. antacids) causes a marked increase in both retention and absorption of amphetamines potentially resulting in dangerously high serum amphetamine levels.[citation needed]
Adderall's effects are similar to other CNS stimulants of the same class and preparation (see amphetamine for details).
Adderall is marketed as either an immediate-release tablet, Adderall, or an extended-release capsule, Adderall XR ("Extended Release"). Doses for both Adderall XR and Adderall are 5, 10, 15, 20, and 30 mg strengths with instant-release Adderall having two extra ones, 7.5 and 12.5 mg, and Adderall XR having a 25 mg dose.[citation needed]
Adderall XR utilizes the Microtrol extended-release delivery system, incorporating two types of beads. The first dissolves immediately, releasing half of the medication, while the second type dissolves much more slowly releasing the remaining medication four hours later. Maximum plasma concentration is achieved in seven hours, compared to instant-release Adderall, which reaches maximum plasma concentration within three hours. As a result of its high bioavailability, Adderall XR's effectiveness is not altered by food absorption in the gastrointestinal tract. However, mean plasma concentration is prolonged by 2.5 hours (using a 900 calorie standard high-fat meal as the control). Medications that alter urinary pH will cause variations in amount and method of excretion and usage should be monitored when taken concurrently with Adderall.[citation needed]
Manufacturer's claims of instant release have been disputed. A US patent granted for Adderall[7] was a pharmaceutical composition patent listing a rapid immediate release oral dosage form. No claim of increased or smooth drug delivery was made. A recent double-blind, placebo-controlled crossover study, conducted among children, indicated that patients behaved similarly to other immediate release amphetamines. The authors found that sustained-release dexamphetamine (the main isomeric-amphetamine component of Adderall) had a longer duration of action, though D-amphetamine was less effective in the first few hours.[8]
Adderall has been commonly prescribed for many years as a treatment for children and adults with attention deficit/hyperactive disorder (ADHD), a disorder that prevents children and adults from being able to focus on tasks for extended periods of time, a particularly detrimental condition for school performance. After administration of Adderall students have been shown to give higher teacher ratings and perform better in mathematics within 1.5 hours of initial dose. Depending on dosage, these beneficial effects can also last several hours allowing improved performance throughout the day.[9][10]
Other studies comparing Adderall with other similar medications have shown that Adderall is also more potent than Ritalin (methylphenidate) and has a longer period of efficaciousness. For many this means it is likely preferable as a medication for ADHD, and certainly a substitute for children who have adverse side effects to Ritalin, or for whom Ritalin has become ineffective.[11][12]
There are also other reasons for taking Adderall aside from just alleviating the symptoms of ADHD. Untreated ADHD has been linked to an increased risk of psychoactive substance abuse later in life.[13]Fortunately, the likelihood of a drug abuse disorder can be approximately halved by proper treatment during childhood. For many, these stimulant medications used to treat ADHD actually provide protection against developing other drug dependencies in this increased risk population. This contradicts the commonly held misconception that use of drugs like Adderall or Ritalin can cause increased drug dependency later in life.[14]
However, specialists also stress the need for ADHD treatments not to solely rely on drugs like Adderall. They advise a comprehensive treatment plan that includes ADHD education, coaching and support groups; regular visits to your doctor; therapy or counseling regarding ADHD; involvement in recovery programs, and family and relationship counseling when appropriate.[15]
Until recently, the closest generic equivalent to Adderall (which uses racemic mixed amphetamine salts) was dextroamphetamine sulfate also known as Dexedrine and available in a sustained release form called Dexedrine ER. As of 2008, mixed amphetamine salts are available as a generic formulation[16]. It should be noted that Dexedrine is a single salt form of D-amphetamine, therefore Dexedrine and Dexedrine ER are not strict generic equivalents for Adderall and Adderall XR, though they may, in terms of physiological and psychological effects, be a de facto generic alternative. The savings between Adderall XR and generic Dexedrine ER are significant: 90 dextroamphetamine extended-release capsules cost $20 at a retail pharmacy in the United States, while the equivalent 90 Adderall XR capsules cost approximately $420[17]. The difference is because Adderall XR has been protected under patent in the United States. Until this patent expires, generic versions of Adderall XR will not become available. The generic formulation of Adderall, however, marketed as "mixed amphetamine salts" or "d-amphetamine salt combo," carry a significant savings over that of branded Adderall. On average, Adderall runs about $330 per 100 doses (or $3.30 per dose), whereas the generic mixed amphetamine salts are about one third as expensive - running about $120 per 100 doses (or a little more than $1 per dose).[16]
Vyvanse is another alternative which is actually a prodrug (precursor) of dextroamphetamine. It behaves differently in the body than other formulations of amphetamines because in its parent form is not directly biologically active as an amphetamine (see Dextroamphetamine at "Formulations"). Vyvanse costs about $500 for 100 doses.[16]
Adderall’s inclusion of levoamphetamine provides the pharmaceutical with a quicker onset and longer clinical effect compared to pharmaceuticals exclusively formulated of dextroamphetamine.[18] Although it seems that where the human brain has a preference for dextroamphetamine over levoamphetamine, it has been reported that certain children have a better clinical response to levoamphetamine.[19]
Amphetamines are believed to exert their effects by binding to the monoamine transporters and increasing extracellular levels of the biogenic amines dopamine, norepinephrine and serotonin.
It is hypothesized that D-amphetamine acts primarily on the dopaminergic (DA) systems, while L-amphetamine is comparatively norepinephrinergic (NE). The primary reinforcing and behavioral-stimulant effects of amphetamine, however, are linked to enhanced dopaminergic activity, primarily in the mesolimbic dopaminergic pathway. Amphetamine binds to the dopamine transporter (DAT) and blocks the transporters ability to clear DA from the synaptic space. In addition, amphetamine is transported into the cell which leads to dopamine efflux (DA is transported out of the cell and into the synaptic space via reverse transport of the DAT).
Amphetamine also possesses the ability to inhibit the enzymes monoamine oxidase A and B (MAO-A and MAO-B) in high doses. MAO-A is responsible for the break down of serotonin, dopamine, norepinephrine and epinephrine. MAO-B is responsible for breaking down dopamine (more potently than MAO-A) and phenylethylamine (PEA), which has actions similar to amphetamine itself and is thought to be involved in feelings of lust, confidence, obsession and sexuality. Some of the first antidepressants successfully marketed are in fact Monoamine Oxidase inhibitors. However, MAO inhibition seen with amphetamine is neither substantial enough in duration and quantity to entail the need for a tyramine limited diet, unlike the more potent and long lived MAO inhibiting antidepressants.
Amphetamine's ability to cause the inhibition of MAO results in the accumulation of monoamines while amphetamine also directly stimulates the release of these neurochemicals, resulting in a potent elevation in monoamine neurotransmission. In sum, the effect of amphetamines is to increase neurotransmitter availability in the synapse by both causing more neurotransmitter to be released as well as prolonging its availability in the synapse by slowing its removal.
These symptoms require immediate medical assistance:
Tolerance, extreme psychological dependence, and severe social disability can occur when amphetamines are abused. The manufacturer warns against exceeding the prescribed dosage, injecting the drug, or insufflation of the drug. Prolonged high doses of amphetamines followed by an abrupt cessation can result in extreme fatigue and mental depression. Chronic abuse of amphetamines can result in the manifestation of amphetamine psychosis.[6]
The following provides only general guidelines and is not comprehensive. Please refer to a more comprehensive list for further information regarding co-administration of amphetamine with other substances.
Due to side effects including appetite suppression and weight loss, Adderall has also been used as an off-label drug for obesity.[20]
Adderall is also reportedly widely used as a "study drug" at many American universities. Adderall is reported to help focus energy and concentration to a much higher level than normal. It enables the user to focus and stay awake.[21] Stories of students writing papers for an unusual number of continuous hours [e.g., 14 hours], or cramming all night for an exam with no loss of energy or concentrations are common. However, the user reportedly can suffer from drastic side effects the following day if Adderall was used to avoid a normal sleep pattern. "In extreme cases, the drug can cause paranoia, hallucinations and heart attacks."[21] William Frankenberger, psychology professor at University of Wisconsin at Eau Claire, led at a study at the university in 2004 that reported 14% of the campus had abused some form of ADHD drug, including Adderall.[21]. College campuses known to be highly competitive or have a high rate of binge drinking had up to 25% of students who misused an ADHD medication within one year, a survey of students at 119 colleges across the country concluded.[21]. Other forms of ADHD medication used as a performance enhancing drug include Ritalin, Concerta, and Dexedrine.[22].
The Nevada State Athletic Commission has banned athletes in the state from using Adderall. Tim Credeur was removed from a UFC fight on the finale of The Ultimate Fighter 7 because of a positive drug test due to his use of it.
On February 9, 2005, Health Canada suspended all sales of Adderall XR after data collected by manufacturer Shire Pharmaceuticals linked the drug to 12 sudden deaths in American children.[23] Further research found data suggesting use of Adderall resulted in an increased risk of cardiac defect. Given the more than 37,000,000 prescriptions for Adderall filled during the four years, the U.S. Food and Drug Administration could find no increased risk of sudden death among Adderall users beyond the normal rate of the general population.[24][25] In August 2005, Health Canada followed the committee report of three independent physicians and lifted the ban on Adderall XR.[26][27] Given that persons with ADHD are more likely to engage in risky or dangerous behavior, it has been suggested that stimulant medications for persons with ADHD may actually result in lower incidence of premature death.[28] The use of Adderall is generally not advised in those persons with pre-existing cardiac or mental illnesses. It is also not advised in persons who have a history of drug abuse.[29] Although FDA safety advisors voted 8 to 7 to issue a black box warning, the FDA's pediatric advisory committee refused to give the drug its most severe black box warning in March 2006.[30] A Black Box Warning regarding amphetamine abuse potential is in place, however. In September 2008, Britain's National Institute for Health and Clinical Excellence urged physicians not to prescribe Adderall or similar drugs to children under 5, and to exhaustively consider other approaches to behavioral modification before prescribing such drugs to children 5 and up. [31]
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