Amphetamine

Attention Deficit Hyperactivity Disorder (ADHD)

Amphetamine is commonly prescribed to treat ADHD in children and adults. It works by changing the levels of certain natural substances in the brain that help control impulses and attention. When used for ADHD, it may help to:

• Increase the ability to pay attention and stay focused.
• Decrease impulsivity and hyperactivity.
• Improve listening skills and organization.

It is typically used as part of a comprehensive treatment plan that may include social, educational, and psychological therapies.

Narcolepsy

This medication is also used to treat narcolepsy, a sleep disorder characterized by excessive daytime sleepiness and sudden, uncontrollable episodes of falling asleep. Amphetamine helps individuals with narcolepsy stay awake during their normal waking hours.

Mechanism of Action

Amphetamines function by stimulating the central nervous system. They primarily affect the brain by increasing the activity of two key neurotransmitters: dopamine and norepinephrine. These chemicals are responsible for transmitting signals between nerve cells and play a significant role in how the brain manages focus, alertness, and impulse control.

The medication works in two main ways:

• Increasing Release: It prompts the brain to release higher amounts of dopamine and norepinephrine.
• Blocking Reuptake: It prevents these chemicals from being reabsorbed back into the nerve cells too quickly, allowing them to remain active in the brain for a longer period.

While the exact way amphetamines produce their therapeutic effects in conditions like attention deficit hyperactivity disorder (ADHD) is not fully understood, it is believed that increasing these chemical levels helps improve concentration and decrease impulsivity. In conditions like narcolepsy, this stimulation helps the brain maintain a state of wakefulness and reduces excessive sleepiness during the day.

Common Side Effects

• Dry mouth
• Loss of appetite and weight loss
• Stomach pain, nausea, or vomiting
• Dizziness or headache
• Nervousness, restlessness, or difficulty falling asleep
• Fast heartbeat
• Diarrhea or constipation
• Changes in sexual drive or ability

Serious Side Effects

Seek medical attention immediately if you experience any of the following serious symptoms:

• Signs of heart problems, such as chest pain, shortness of breath, or fainting
• Signs of a stroke, such as sudden weakness or numbness (especially on one side of the body) or slurred speech
• Seizures
• Vision changes or blurred vision
• Mental or mood changes, including hallucinations, paranoia, or extreme agitation
• New or worsening motor or vocal tics
• Circulation problems in the fingers or toes, which may cause numbness, pain, or skin color changes from pale to blue or red
• Unexplained muscle pain or weakness

Abuse and Dependence

Amphetamine is classified as a controlled substance because it has a high potential for misuse, abuse, and addiction. Long-term use can lead to physical and psychological dependence. Misuse of this medication may cause serious heart problems or sudden death.

Cardiovascular Risks

Serious heart-related problems have been reported, including sudden death in people with structural heart defects or other serious heart conditions. This medication can also increase blood pressure and heart rate. It is generally avoided in individuals with:

• Advanced hardening of the arteries (arteriosclerosis)
• Symptomatic heart disease
• Moderate to severe high blood pressure
• A history of stroke or heart attack

Psychiatric Symptoms

Amphetamine may cause or worsen psychiatric symptoms. This includes:

• Psychosis or Mania: New symptoms such as hearing voices, believing things that are not true, or becoming unusually suspicious may occur, even in people without a history of these issues.
• Bipolar Disorder: It may trigger mixed or manic episodes in people with bipolar disorder.
• Aggression: Some patients, especially children, may experience increased aggression or hostility.

Growth and Development

In children and adolescents, long-term use of stimulants may be associated with a temporary slowing of growth. Healthcare providers typically monitor height and weight during treatment.

Serotonin Syndrome

A potentially life-threatening condition called serotonin syndrome can occur, especially when amphetamine is taken with other medications that affect serotonin levels, such as certain antidepressants or monoamine oxidase inhibitors (MAOIs).

Other Precautions

This medication is contraindicated for use in people with glaucoma, overactive thyroid (hyperthyroidism), or a history of drug abuse. It should not be used within 14 days of taking an MAOI. It may also lower the seizure threshold in patients with a history of seizures.

Pregnancy

Using amphetamines during pregnancy may lead to an increased risk of premature birth and low birth weight. Infants born to individuals who take these medications may also experience withdrawal symptoms, including agitation or excessive tiredness, shortly after birth.

It is not fully established whether amphetamines cause birth defects when taken at therapeutic doses. Because of the potential risks, healthcare providers typically only prescribe this medication during pregnancy if the potential benefit justifies the potential risk to the fetus. If you become pregnant while taking this medication, contact your doctor to discuss your treatment plan.

Breastfeeding

Amphetamines are excreted into human breast milk. Because these drugs can cause serious side effects in a nursing infant, healthcare providers generally recommend that individuals refrain from breastfeeding while taking amphetamines. It is important to talk with a healthcare professional about the safest way to feed your baby if you require treatment with this medication.

Oral Formulations

Amphetamine is primarily available in oral forms designed for different absorption rates. The choice of formulation depends on the condition being treated and the required duration of effect. Common forms include:

• Immediate-release tablets: These release the medication into the system quickly and are often taken multiple times throughout the day.
• Extended-release capsules: These are designed to release the medication slowly over several hours, typically allowing for once-daily dosing.
• Extended-release oral suspension: A liquid form of the medication that provides a steady release of the drug over time, often used for patients who have difficulty swallowing pills.
• Orally disintegrating tablets: These tablets are designed to dissolve on the tongue without the need for water.

Strengths

The strengths of amphetamine products vary significantly based on the specific formulation and release mechanism. Tablets and capsules are available in a wide range of milligram strengths to allow for precise dosage adjustments by a healthcare provider. Liquid formulations are measured by the amount of medication contained in each milliliter of the suspension.

FDA Approval and Indications

The U.S. Food and Drug Administration (FDA) has approved amphetamine and its derivatives for the treatment of specific medical conditions, including:

• Attention Deficit Hyperactivity Disorder (ADHD)
• Narcolepsy

Boxed Warning

Amphetamine products carry a boxed warning due to their high potential for abuse and misuse. The FDA requires this warning to alert healthcare providers and patients that prolonged use can lead to drug dependence. Furthermore, misuse of amphetamines may cause serious cardiovascular adverse events and sudden death.

Controlled Substance Status

Amphetamine is classified by the Drug Enforcement Administration (DEA) as a Schedule II controlled substance. This designation is reserved for drugs with a high potential for abuse and severe psychological or physical dependence. Consequently, prescriptions are subject to strict regulatory controls, including limitations on refills and specific prescribing requirements.

Patient Safety Information

To ensure safe use, the FDA requires that a Medication Guide be dispensed with every prescription. This document provides essential information regarding the risks of heart-related problems, psychiatric symptoms, and the potential for abuse or withdrawal.

Risk of Misuse and Dependence

Amphetamine is classified as a substance with a high potential for misuse. It can be habit-forming, especially when taken in higher doses or for longer periods than prescribed. Misuse of this medication can lead to serious health complications, including severe heart problems and sudden death.

Tolerance and Withdrawal

With regular use, the body may develop a tolerance, meaning higher doses are required to achieve the same effect. If use is stopped suddenly after long-term use, withdrawal symptoms may occur. These symptoms often include:

• Extreme tiredness or fatigue
• Depression or low mood
• Sleep disturbances, such as insomnia or oversleeping
• Increased appetite

Psychological Effects

Chronic misuse of amphetamines can lead to significant psychological changes. Some individuals may experience amphetamine psychosis, which is characterized by symptoms such as paranoia, delusions, and hallucinations. These effects may persist even after the drug is no longer being used.