Adderall and Vyvanse are both stimulants proven to be useful for the treatment of ADHD/ADD. However, they differ in their mechanisms of action and their effects can vary among individuals. Read on to see if Adderall or Vyvanse is right for you.
Disclaimer: By writing this post, we are not recommending this drug. Some of our readers who were already taking the drug requested that we commission a post on it, and we are simply providing information that is available in the scientific and clinical literature. Please discuss your medications with your doctor.
What are Adderall and Vyvanse?
Adderall (dextroamphetamine-amphetamine) and Vyvanse (lisdexamfetamine) both belong to a class of drug called amphetamines. They are both stimulants that have been proven to be beneficial in the treatment of ADHD/ADD [1, 2, 3].
American adults who take Adderall for ADHD have increased by 90% from 2002 to 2005. Vyvanse is not as commonly used and was approved for use in children in 2007, in adults in 2008, and in adolescents in 2010 [8, 9, 10].
Increased use can cause addiction and abuse. Stimulants have become the second most-misused/abused drug by college students. This stems from a belief that stimulants like Adderall are “harmless” (they are not) [1, 11, 12].
Adderall is also FDA-approved to treat the symptoms of narcolepsy (excessive daytime sleepiness), while Vyvanse is also FDA-approved to treat binge eating disorders .
Both Adderall and Vyvanse are Schedule II drugs, meaning they pose a high risk of abuse that may lead to physical and/or psychological dependence .
Adderall and Vyvanse differ in their amphetamine composition. Adderall is composed of :
- Dextroamphetamine (d-amphetamine) saccharate
- D-amphetamine sulfate
- Levoamphetamine (l-amphetamine) sulfate
- L-amphetamine aspartate
D- and l-amphetamine are mirror images of each other. Adderall contains both molecules because the body processes each form differently, and when they are used together, this increases the drugs overall effectiveness [15, 16].
Vyvanse is only made up of lisdexamfetamine dimesylate. It is classified as a “prodrug” because it does not enter the body in its active form. Once inside the body, prodrugs are converted into their active forms. Vyvanse is converted to d-amphetamine, one of the components of Adderall .
The time to maximum concentration (Tmax) in the body for Vyvanse is 1 hour and the Tmax for d-amphetamine (after conversion from lisdexamfetamine) is 3.5 hours. The Tmax is the time it takes for a drug to reach maximum concentration in the blood. Theoretically, this is when drugs are thought to have their maximal effect .
However, in a study (double-blind randomized controlled trial) of 50 children with ADHD, the Tmax of d-amphetamine (lisdexamfetamine) was closer to 5 hours .
In the same study, the Tmax of d-amphetamine from extended-release Adderall (Adderall XR) was 6.6 hours. The Tmax values varied 3.5 times more for Adderall than Vyvanse. The fluctuating absorption characteristics of Adderall makes Vyvanse more predictable and easier to use [17, 18].
Cell and rodent studies found that Vyvanse was absorbed in the small intestine, and then converted to d-amphetamine by red blood cells. This conversion happens through a process called enzymatic hydrolysis, which is the breakdown of a molecule in the presence of water with the help of an enzyme [3, 19].
Mechanisms of Action
Adderall and Vyvanse are nervous system stimulants. They cause the release of norepinephrine by stimulating α- and β-adrenergic receptors. Adrenergic receptors are those that specifically release neurotransmitters noradrenaline (adrenaline) [20, 21].
Stimulating the α-adrenergic receptor sites causes :
- Constriction of blood vessels all over the body
Stimulating the β-adrenergic receptor sites increases :
- Heart rate
- Muscle blood flow
- The output of blood from the heart
All of these effects help to stimulate the brain into a more active state .
Amphetamines also release adrenaline in the body, which results in increased energy levels .
In a study of 16 volunteers, d-amphetamine was 2 times more effective than l-amphetamine in increasing euphoric mood. Depression following amphetamine use was higher with l-amphetamine .
Rat studies showed that d-amphetamine was better at improving overactivity and impulsiveness while l-amphetamine was more successful in improving sustained attention. Therefore, Vyvanse, which only increases d-amphetamine concentrations, may not be effective in improving sustained attention .
Adderall and Vyvanse both prevent neurotransmitters from being taken up, broken down, and stored inside neurons. This is achieved by blocking transporters that bring molecules from the outside of the cell to the inside of the cell. Specifically, Adderall blocks [24, 3]:
- The dopamine reuptake transporter: It increases dopamine concentrations outside of the cell
- The noradrenaline reuptake transporter: It increases noradrenaline concentrations outside of the cell
Amphetamines also prevent the storage of dopamine in compartments within the cell (vesicles). This increases the availability of dopamine for later use .
Adderall inhibits the activity of proteins that break down dopamine (monoamine oxidase A and B), which further increases the amount of dopamine available for use in the brain .
1) Improve ADHD and ADD
Vyvanse is also widely used and was effective in 74% of children with ADHD, based on a study of 52 children. The same study also tested Adderall, but only found a 72% effective rate .
In the same study, both Adderall and Vyvanse treated ADHD better than placebo. The SKAMP rating scale, which measures ADHD symptoms in the classroom, was equivalent in both Adderall and Vyvanse. Math scores improved slightly more with Adderall than Vyvanse .
On the other hand, symptom severity improved better in Vyvanse. Studies reported 32% of children were “very much improved” with Vyvanse compared to the 16% with Adderall. However, 56% were “much improved” with Adderall compared to 42% with Vyvanse. The rate of side effects was similar in both groups .
Therefore, Vyvanse may improve symptoms better in some children, but Adderall has a wider range of efficacy. This could be due to the mix of amphetamines in Adderall compared to the sole d-amphetamine in Vyvanse.
Adderall is only used for short-term management of ADHD in adults. Long-term use in adults/adolescents has not been proven to be helpful. However, Vyvanse has been shown to be effective long-term in a study of 349 adults with ADHD. [25, 27, 3].
2) Increase Focus
Most people that use Adderall or Vyvanse medically use it to increase focus due to conditions such as ADHD or ADD. Vyvanse may be more useful for adults in workplace settings as the drug’s effects can last up to 14 hours with 1 dose while still being safe and tolerable [1, 3].
The duration of Adderall’s effects is dependent on the type of Adderall taken (extended release or instant release), but it can also potentially last up to 12 hours .
3) Increase Energy Levels
In a study of 12 adults, d-amphetamine, a product of both Vyvanse and Adderall, was better than placebo at increasing energy levels .
However, in rats, d-amphetamine decreased the production of the following energy molecules in the brain :
- Adenosine triphosphate (only at temperatures > 80.6℉)
- Guanosine triphosphate (only at temperatures > 80.6℉)
- Phosphocreatine (only at temperatures > 80.6℉)
These effects were only seen with ambient temperatures greater than 80.6℉ .
D-amphetamine only makes up a portion of Adderall, so it is not a completely accurate representation of Adderall’s effects in increasing energy. However, one can expect these effects following Vyvanse ingestion.
Fatigue can occur following withdrawal from amphetamine use, causing users to re-ingest amphetamine for increased energy .
4) Increase Impulse Control
Improving impulse control can also help decrease weight. In a study of 259 adults with binge eating disorder (BED), 50 and 70 mg Vyvanse led to 10.8 lbs. weight loss in BED patients by decreasing impulsive behavior to binge eat .
A study of 56 ADHD patients given Adderall also caused weight loss by decreasing impulsivity .
5) May Cause Weight Loss
Before Adderall was used for ADHD, it was prescribed to help reduce weight by decreasing appetite. It is not advised to reduce weight using Vyvanse, although this effect can be seen in 9.2 to 21.9% of children [32, 33].
Although Adderall-induced weight loss is usually not severe, it may lead to anorexia. A study of 584 children found that anorexia occurred in 21.9% of the children. Similarly, a study of 287 teens found anorexia to occur in 35.6% of patients [34, 35, 31].
In a study of 259 adults with binge eating disorder, Vyvanse caused 10.8 lbs. of weight loss by the end of the 11–week study. However, the studies were not long-term and mainly done in women. Therefore, extrapolating these findings to the greater population may be unwarranted .
In some rare cases, Adderall may actually cause weight gain. A case study of an 11-year old boy saw Adderall use increase the boy’s weight by 8.8 lbs. in 6 weeks. Changing the timing of Adderall consumption from right after meals to 45 minutes before meals helped to normalize weight gain .
Different Uses of Adderall vs. Vyvanse
Some uses of Adderall that have not been approved for Vyvanse include [36, R]:
- Hyperactivity (in those with ADHD)
Narcolepsy is a disorder that causes extreme daytime drowsiness. A form of Adderall, Adderall XR, is preferred, as it works for longer periods of time and has a lower potential for abuse .
In a study of 18 children suffering from hyperactivity and aggression, Adderall decreased symptoms in 14 of the children .
- Improving driving (in those with ADHD)
- Binge eating disorder (BED)
In a study of 61 ADHD patients, Vyvanse produced fewer accidents and faster reaction times than placebo in driving simulations .
On the other hand, Adderall may worsen driving performance as seen in a study of 25 volunteers. Studies of ADHD drivers given Adderall need to be accomplished .
Vyvanse is the only medication approved by the U.S. Food and Drug Administration for binge eating disorder (BED). In a study of 259 BED adults, 70 mg Vyvanse decreased binge eating episodes from 4.6/week to 0.5/week .
Rat studies show that Vyvanse decreased chocolate binge eating by 71%. It is hypothesized that Vyvanse inhibits the removal of dopamine and norepinephrine and concurrently promotes the release of dopamine, norepinephrine, and serotonin. These neurotransmitters are heavily involved in regulating eating behaviors [40, 13, 41, 42].
Adderall and Vyvanse Misuse/Abuse
In a survey of non-prescription stimulant student users, 93.5% used stimulants to increase focus when studying .
Students who misuse/abuse these amphetamine stimulants report :
- Improvements in mood
- Motivation to work
- Less time needed to accomplish tasks
- Increased physical and mental energy
A survey of 10,000 patients found that Vyvanse was abused at lower rates than both extended and immediate release Adderall .
Surveys of stimulant abusers have found that Vyvanse generally is not liked, leading to less potential for abuse. In fact, Vyvanse was liked even less than placebo, which is uncommon for euphoria-producing drugs. The euphoric effects of Vyvanse are lower due to the time it takes to convert to d-amphetamine [9, 44].
Abuse of amphetamines can cause psychosis, heart attack, diseased heart muscle, and even sudden death. They can also cause long-term increases in heart rate and short-term increases in blood pressure .
Adderall use can cause dependence, which can then lead to withdrawal symptoms when medication is ceased. Withdrawal can lead to :
- Loss of appetite
- Dry mouth
- Stomach pain
- Nausea, vomiting, or diarrhea
- Weight loss (weight loss can be countered through other medications such as cyproheptadine or through a higher caloric diet) 
- A headache
- Increased heart rate
- Seizures (convulsions)
- Changes in vision or blurred vision
- Allergic reactions (symptoms can include itching or hives, swelling in the mouth, face, or hands, difficulty breathing, feeling like you are about to pass out, or tightness in the chest)
- Fever or sweating
- Muscle problems, such as spasms or twitching
- Hallucinations (visual and auditory)
- Unusual mood or behavior
- Signs of heart problems (can be fast, slow, or uneven heartbeats)
- Signs of circulation problems (unexplained bruises, numbness, cold, color changes, or pain in fingers or toes)
Adderall may decrease short-term memory .
It may also lead to antisocial feelings, keeping users from enjoying or participating in interactions with others .
Some of the mental side effects of amphetamine use occur due to too much dopamine in the brain. In a study of 14 patients, 12 patients dependant on amphetamines developed psychosis. This brought about schizophrenic-like paranoia and intense hallucinations [46, 47].
Adderall use by athletes may be dangerous as it increases body temperatures, which may cause heat stress. It is especially dangerous during exercise for long periods of time because it is easy to miss the symptoms of exhaustion and fatigue .
Use of stimulants can also stunt growth. A long-term study of 281 children taking Vyvanse found that, on average, height decreased by 13%. However, discontinuing treatment can possibly lead to a growth “rebound” [48, 49].
Adderall and Vyvanse May Increase Your Risk of Heart Problems
One of the most dangerous side effects of both Adderall and Vyvanse can be a heart attack or stroke. Patients with a personal or family history of heart conditions are at a higher risk of developing such complications [50, 51, 3].
The heart problems can be due to changes in heart rate and blood pressure that are seen following Adderall or Vyvanse consumption. On average, Adderall increases heart rate 1 to 2 beats per minute (bpm). As the dose is increased, heart rate increases respectively [52, 14, 3].
In a study of 111 children with ADHD, Vyvanse increased heart rate by up to 6.6 bpm. The average blood pressure also rose by up to 4 mmHg .
Adderall release is dependent on the acidity of the stomach. In a study of 24 healthy adults, when Adderall was given with omeprazole (reduces stomach acid), Tmax of Adderall decreased by 2.25 hours. The Tmax of Vyvanse in response to omeprazole did not change, suggesting that Vyvanse is not affected by changes in acidity .
Because Vyvanse is unaffected by pH changes, it has fewer drug-drug interactions .
However, the following Adderall drug interactions may also apply to Vyvanse. Please tell your doctor about all drugs, medicines, supplements, etc. you are taking before taking Adderall or Vyvanse :
- Ammonium chloride
- Glutamic acid
- Sodium acid phosphate
- St. John’s Wort
- Tryptophan supplements
- Allergy medicine
- Sodium bicarbonate
- Blood pressure medications
- Migraine medications
- Monoamine oxidase inhibitors
The different doses of Adderall sold are 5 mg, 7.5 mg, 10 mg, 12.5 mg, 15 mg, 20 mg, and 30 mg. They may be in tablet form or the extended release form. Extended-release capsules are labeled Adderall XR while instant release tablets are labeled Adderall IR .
A 70 mg dose of Vyvanse is therapeutically equivalent to a 30 mg Adderall XR tablet .
Vyvanse is a long-acting pill. To achieve long-term duration, Adderall XR must be taken instead of Adderall IR .
It comes in capsule form in 10 mg, 20 mg, 30 mg, 40 mg, 50 mg, 60 mg, and 70 mg doses and as a chewable tablet in the same dosage strengths except there is no 70 mg chewable tablet.
In a study of 18 adult volunteers, taking Vyvanse in capsule form or as a solution did not change the exposure to the drug. Eating food did not alter the exposure either except for high-fat meals, which prolonged the exposure by around one hour [3, 59].
For children who have trouble swallowing pills, opening the Vyvanse capsule and dissolving the contents in water or juice may be a better option. For Adderall, breaking open the capsule over applesauce and ingesting with it is a viable option [3, 28].
Limitations and Caveats
It is difficult to say for certain which stimulant is better: Adderall or Vyvanse. There are not many studies studying the two drugs in comparison. When compared, Adderall is better for some symptoms and situations and Vyvanse is better in others [25, 26, 17].
Furthermore, many of the clinical trials are performed on healthy people, which is not what one would see in regular practice. The limited number of long-term studies and the number of patients in the studies also makes it difficult to find rare adverse events .
Vyvanse has not been proven to be safe and effective for children ages 3 to 5 .