• Talking about drugs
• Reducing risk
• Drug Facts
• Resources

• Insights
• Programs
• Advocacy
• About

• Accessibility
• Help & Support
• Search

• Drug List
• Drug Wheel
• Stimulants
• Dexamphetamine

Last published: August 15, 2025

ALCOHOL & DRUG HOTLINE

1800 250 015

Drug List

Drug Wheel

Stimulants

Dexamphetamine

Search drug name, slang or effect.

Dexamphetamine

On this page

Last published: August 15, 2025

What is dexamphetamine?

Dexamphetamine is a stimulant drug, which means it speeds up the messages travelling between the brain and body.2

Dexamphetamine is a medication prescribed to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy (a sleep disorder).1 Dexamphetamine is a Schedule 8 drug in Australia which means it is tightly controlled and requires a prescription.3

Dexamphetamine is also sometimes used by people without a prescription to increase alertness or to get ‘high’.4

What does dexamphetamine look like?

Dexamphetamine is usually a small, round, white tablet. It can also be a capsule and can come in short acting or long acting forms.6

Other names

Dexamphetamine Sulfate (Sigma), Dextroamphetamine, Dexamfetamine, lisdexamfetamine, Vyvanse, dexies, dex.

Other types of stimulants

Amphetamines

Betel nut

Caffeine

Cocaine

Crystal Methamphetamine (Ice)

Khat

Synthetic cathinones

Tobacco

How is dexamphetamine used?

Dexamphetamine is usually swallowed or crushed and snorted, but is sometimes injected or smoked/inhaled.7

Effects of dexamphetamine

Use of any drug can have risks. It’s important to be careful when taking any type of drug.

Prescribed stimulants work on the parts of the brain involved in regulating attention and arousal (being alert and awake). The medications can greatly improve concentration, impulse control and hyperactivity in about 80% of children with ADHD.8

In adults, attention deficit hyperactivity disorder is quite different —and the symptoms are unique for each individual.9 It is estimated that around 533,300 adults (aged 20+) have ADHD in Australia.10

Dexamphetamine affects everyone differently based on:

size, weight and health

whether the person is used to taking it

whether other drugs are taken around the same time

the amount taken.

The effects of dexamphetamine may include:

enhanced mood and/or motivation

increased energy and/or confidence

increased alertness and/or focus

fast heartbeat.11

Side effects may include:

nausea

vomiting

abdominal pain

headache

dizziness

mood changes such as depression or irritability

increased heart rate and blood pressure

heart palpitations

restlessness, nervousness, tremor

sleep difficulties

loss of appetite, or weight loss.3

Side effects are generally mild and more likely to occur during the first few days of treatment, and may disappear as the body adjusts.3

The effects of the short acting tablet can last around 4 to 6 hours and the long acting can last for approximately 8 to 12 hours.12

Overdose

If you take more than the recommended dose you could overdose.

Call an ambulance straight away by dialling triple zero (000) if you, or someone else, has any of the following symptoms (Emergency services are there to help and can provide instructions over the phone):

nausea & vomiting

diarrhoea

chills

sweating

headache

pain or tightness in the chest

shortness of breath

fast, irregular heartbeat

seizures (fits)

weakness in the limbs or face

confusion, delusion or hallucinations.3

Coming down

Experiencing comedown effects is less likely when dexamphetamine is taken as prescribed, but some people may still experience a comedown or ‘crash’ after use.13-16

Comedown effects can be more likely when dexamphetamine isn’t taken as prescribed (also called non-prescribed use) and can include feeling exhausted, restless sleep, irritability and anxiety.13-16

If you experience any effects that worry you, speak with your prescribing doctor or specialist.

Long-term effects

Regular use of dexamphetamine over a long-period has been linked to:

cardiovascular complications

reduced growth (weight and height) in children.13,14

Dexamphetamine and mental health

For some people, dexamphetamine use can lead to:

increased anxiety

trouble sleeping/insomnia

psychosis/psychotic symptoms.18

The risk of experiencing psychosis or psychotic symptoms is higher when dexamphetamine isn’t taken as prescribed, especially for long periods at high doses. Psychosis is when someone loses the ability to distinguish between what is real and what isn’t real. It can includes symptoms such as paranoia, delusions, and hallucinations.19,20

If you have a history of anxiety, insomnia or psychosis, speak with your prescribing doctor about whether dexamphetamine is suitable.18

Tolerance and dependence

For people who take dexamphetamine as prescribed, they may feel they depend on them to manage their condition and/or regular functioning. It’s also possible to build up a tolerance, where they may feel like they need higher doses to manage their condition.21 If you have any concerns around tolerance or dependence, speak with your prescribing doctor.

People who regularly use dexamphetamine not as prescribed can develop tolerance and become dependent on the drug.

Mixing dexamphetamine with other drugs

Mixing dexamphetamine with other drugs can have unpredictable effects and increase the risk of harm.

Dexamphetamine and other stimulants (speed, ice, caffeine, cocaine etc.): Combined stimulants increase strain on heart, anxiety & risk of stroke.

Dexamphetamine and alcohol: may feel less intoxicated due to stimulant effects of amphetamine and lead to drinking more. Increases risk of alcohol poisoning.

Dexamphetamine and tricyclic antidepressants/MAOI inhibitors: increased heart rate and blood pressure.22,23