What is the Difference Between Ritalin and Dexamphetamine

The key difference between Ritalin and dexamphetamine is that Ritalin primarily blocks the reuptake of dopamine and norepinephrine, while dexamphetamine not only blocks reuptake but also reverses the effect of transporters and competitively inhibits the vesicular monoamine transporter to increase dopamine and norepinephrine levels in the synaptic cleft.

Ritalin and dexamphetamine are central nervous system (CNS) stimulants for treating attention deficit hyperactivity disorder (ADHD) and narcolepsy. However, these drugs are commonly known for their high potential for abuse (Schedule II drugs), leading to severe psychological and physiological dependence. Both Ritalin and dexamphetamine are orally administered either as capsules or tablets. Ritalin primarily works by inhibiting the reuptake of dopamine and norepinephrine, while dexamphetamine releases dopamine and norepinephrine to the synaptic clefts in the striatum. The rational selection of Ritalin and dexamphetamine depends on individual factors and treatment goals, and a healthcare professional should decide.

CONTENTS

1. Overview and Key Difference
2. What is Ritalin 
3. What is Dexamphetamine
4. Similarities – Ritalin and Dexamphetamine
5. Ritalin vs. Dexamphetamine in Tabular Form
6. Summary – Ritalin vs Dexamphetamine

What is Ritalin?

Ritalin is the most prevalent medication for ADHD and narcolepsy, increasing dopamine and norepinephrine availability by inhibiting their reuptake. The active ingredient of Ritalin is methylphenidate, which belongs to the class of amphetamine drugs. It is a racemate of a 1:1 proportion of d-threo methylphenidate and l-threo methylphenidate, and the pharmacological effect entirely depends on the d-threo isomer. The studies suggest the half-life of Ritalin ranges around 3.5 h, and the peak level in the brain reaches 60 min after oral administration.

The drug is generally recommended before a meal, which helps to improve the rate of reaching peak plasma concentration and reducing the adverse side effects. Ritalin is known to cross the blood-brain barrier through a free diffusion mechanism of nonionized lipophilic. The effects are assumed to be related to the blockade of the dopamine D1 receptor and the norepinephrine alpha-2 adrenergic receptor. Monitoring blood pressure, pulse, insomnia, and mood changes is recommended during the treatment.

What is Dexamphetamine?

Dexamphetamine is a noncatecholamine, sympathomimetic amine that acts as another CNS stimulant in the drug class of amphetamine. The drug increases the levels of dopamine and norepinephrine in the synaptic clefts in the striatum and is used to treat ADHD and narcolepsy. The increased levels of dopamine and norepinephrine in the synaptic clefts by dexamphetamine are attributed to the inhibition of the reuptake of dopamine and norepinephrine, reversing the function of dopamine and norepinephrine and inhibiting vesicular monoamine transporters. Dexamphetamine can be taken with or without a meal and is metabolized by cytochrome p-450 2D6 in the liver and later conjugated by sulfotransferase or glucuronosyltransferase, and one-third of the drug is eliminated through renal clearance.

Dexamphetamine is readily absorbed in the gastrointestinal tract and distributed into the brain and cerebrospinal fluid with a high concentration. Recent studies have revealed that oral administration of 5 mg tablet initiates the onset of action between 30 min to 2 h with a half-life of 12-13 h. In addition, the oral intake of 5-30 mg of dexamphetamine is associated with reduced appetite, increased arousal, elevation of mood, and improved concentration and self-confidence. It is not recommended to use dexamphetamine during breastfeeding. Since the long-term effect has not been examined in pediatric patients, it should be avoided in children under three years.

What are the Similarities Between Ritalin and Dexamphetamine?

• Ritalin and dexamphetamine are central nervous system (CNS) stimulants.
• They work by increasing neurotransmitters in the brain, particularly dopamine and norepinephrine.
• Both medications are approved for treating attention deficit hyperactivity disorder (ADHD) and narcolepsy.
• Both Ritalin and dexamphetamine have effectively reduced ADHD and narcolepsy symptoms in clinical studies.
• They exhibit common side effects, including increased heart rate, elevated blood pressure, decreased appetite, insomnia, nervousness, irritability, and gastrointestinal disturbances.

What is the Difference Between Ritalin and Dexamphetamine?

Ritalin and dexamphetamine are medications used to treat ADHD and narcolepsy. However, there is a significant difference between Ritalin and Dexamphetamine. Ritalin primarily blocks the dopamine and norepinephrine receptors to prevent the reuptake of dopamine and norepinephrine in the synaptic cleft. In contrast, dexamphetamine blocks the reuptake and reverses the effect of dopamine and norepinephrine receptors, and inhibits the vesicular monoamine transporter to increase dopamine and norepinephrine levels in the synaptic cleft. Additionally, dexamphetamine is comparatively cheap and prescribed as the first-line treatment for pediatric patients. Ritalin is recommended to take before meals; in contrast, no specificity is associated with dexamphetamine. Therefore, it is important to consult a healthcare professional to determine the most suitable medication for an individual’s needs.

Below is a summary of the difference between Ritalin and Dexamphetamine in tabular form for side-by-side comparison.

Summary – Ritalin vs. Dexamphetamine

Ritalin and dexamphetamine are both medications used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. While both drugs are CNS stimulants and increase the levels of dopamine and norepinephrine in the brain, there is a key difference between Ritalin and Dexamphetamine. Ritalin primarily blocks the reuptake of dopamine and norepinephrine, while dexamphetamine blocks reuptake and reverses the effect of the dopamine and norepinephrine transporters and competitively inhibits the vesicular monoamine transporter. Additionally, dexamphetamine is comparatively cheap and prescribed as the first-line treatment for pediatric patients. Other differences include food recommendations. It is important to consult a healthcare professional to determine the most suitable medication for an individual’s needs.

Reference:

1. Efron, Daryl, et al. “Methylphenidate versus Dexamphetamine in Children with Attention Deficit Hyperactivity Disorder: A Double-Blind, Crossover Trial.” Pediatrics, vol. 100, no. 6, 1997.
2. McCreary, Andrew C., et al. “Psychostimulants.” International Review of Neurobiology, 2015, pp. 41–83.

Image Courtesy:

1. “Methylphenidate-2D-skeletal” By Original: Unknown Vector: Jesin – Own work assumed (based on copyright claims). (Public Domain) via Commons Wikimedia
2. “D-amphetamine” By Ring0 – Own work (Public Domain) via Commons Wikimedia