What are uppers and downers?

In this article, we take a closer look at different drug groups and their effects on the body.

Read the full article below.

What are uppers and downers?

‘Uppers’ and ‘downers’ are informal terms used to describe two broad categories of drugs that have opposite effects on the brain and body.

Uppers, also known as stimulant drugs, increase activity in the central nervous system (CNS). They are known for boosting energy, increasing alertness, elevating mood, and raising heart rate and blood pressure. Examples of stimulant drugs include caffeine, cocaine, amphetamines and methamphetamine.

Downers or CNS depressants, slow down brain activity, causing the user to feel relaxed or sedate. Examples of depressants include alcohol, benzodiazepines, cannabis or opioids.

In short, uppers stimulate the body, while downers depress its functions. Both types can have legitimate medical uses but also carry serious risks if abused.

What is the difference between depressants and stimulants?

The key difference between depressants and stimulants lies in how they affect the central nervous system (CNS) and, by extension, the body and mind.

Stimulants (uppers) speed up CNS activity. This leads to increased levels of alertness, energy, and focus. People who take stimulant drugs may experience a surge in motivation, elevated mood, and enhanced physical or mental performance. However, they can also experience side effects such as insomnia, anxiety, irregular heartbeat, and elevated blood pressure, especially when taken in high doses.

Some stimulants are medically prescribed, particularly to treat attention deficit hyperactivity disorder (ADHD), while others are taken illicitly for their euphoric effects.

In contrast, depressants (downers) slow down the CNS. This produces a calming effect, making them useful for treating anxiety, panic disorders, and sleep disturbances.

Depressants reduce brain activity and can cause drowsiness, slowed breathing, and a relaxed state. However, their misuse can lead to dependence, overdose, and in severe cases, life-threatening respiratory failure.

How do uppers (stimulants) affect the central nervous system?

Stimulant drugs work by increasing the activity of certain chemicals, or neurotransmitters, in the central nervous system (CNS) – particularly dopamine and norepinephrine. These chemicals play key roles in attention, motivation, pleasure, and the body’s fight-or-flight response.

When a person takes a stimulant drug, this speeds up the transmission of signals in the brain and spinal cord.

This can lead to:

• Increased alertness
• Enhanced concentration and focus
• Elevated heart rate and blood pressure
• Increased energy levels
• Suppressed appetite
• Elevated mood or euphoria

When prescribed (e.g. to treat ADHD), stimulants can help with concentration. However, when taken illicitly in high doses – without medical supervision – the effects can become dangerous, triggering irregular heartbeat, heightened anxiety, paranoia, and even psychosis.

Over time, regular stimulant use can alter how the brain processes reward and pleasure, increasing the risk of substance abuse and addiction.

Because they directly affect the CNS, stimulants can also interact with other substances, further complicating their impact on mental and physical health.

What are the effects of stimulants?

The effects of stimulants can vary depending on the type of drug, the quantity taken, the method of ingestion (e.g. swallowed, snorted), a person’s age, weight and metabolism, whether they are taking any other drugs, and whether the drug has been prescribed or is being abused recreationally.

Short-term effects of stimulant use can include:

• Increased alertness and energy
• Elevated mood or euphoria
• Faster heart rate
• Increased blood pressure
• Dilated pupils
• Reduced appetite
• Improved focus and mental clarity (especially in people with ADHD)
• Insomnia and restlessness

The long-term effects of stimulant misuse can include:

• Dependence and addiction
• Chronic sleep issues
• Malnutrition
• Mental health conditions such as depression or anxiety
• Increased risk of heart attack or stroke
• Tremors or muscle twitches
• Impaired thermoregulation – where the body is unable to regulate its own temperature
• Aggressive or erratic behaviour
• Psychosis (in extreme cases)

In cases of substance abuse, users can build up a tolerance, requiring higher doses to feel the same effects – which increases the risk of overdose or other life-threatening complications.

Even prescription stimulants, such as those used to treat ADHD, can be harmful if not taken under proper medical guidance.

What are common examples of uppers/upper drugs?

Uppers, also known as stimulants, include a range of substances that increase activity in the central nervous system (CNS). Some are legally prescribed for medical conditions, such as ADHD or narcolepsy, while others are used recreationally and carry a high risk of substance misuse.

Prescription stimulants (typically used to treat ADHD or narcolepsy)

• Methylphenidate (e.g. Ritalin, Concerta XL)
• Lisdexamfetamine (e.g. Elvanse)
• Dexamfetamine (less commonly prescribed)

These medications are prescribed under the guidance of a healthcare professional and are regulated under Irish controlled drug legislation (such as the Misuse of Drugs Acts 1977 to 2016).

Illicit stimulants

• Cocaine
• MDMA (ecstasy)
• Methamphetamine (crystal meth)

Legal stimulants

• Caffeine – found in coffee, tea, energy drinks, and some medications
• Nicotine – found in cigarettes, vaping products, and tobacco

Order a Home Drug Test Kit Online

What are the signs and symptoms of stimulant use?

Recognising the signs and symptoms of stimulant use can help identify whether someone may be misusing these drugs – whether legally prescribed or obtained illicitly. While some symptoms might be subtle, others can be more pronounced, especially in cases of substance abuse or overdose.

Physical signs may include:

• Dilated pupils
• Increased heart rate and blood pressure
• Rapid breathing
• Sweating or flushed skin
• Loss of appetite and weight loss
• Tremors or twitching
• Dry mouth

Behavioural and psychological signs may include:

• Hyperactivity or restlessness
• Excessive talking or excitement
• Increased alertness and energy
• Anxiety or panic
• Insomnia
• Aggression or irritability
• Paranoia or hallucinations (high doses or prolonged use)

Signs of stimulant overdose or serious misuse include:

• Chest pain
• Confusion or disorientation
• Severe agitation or aggression
• Seizures
• Loss of consciousness
• Life-threatening complications like heart attack or stroke

Although many of these symptoms may be absent when stimulants are taken correctly as prescribed, stimulant misuse (high doses/non-medical use) significantly increases the risk of harmful effects.

Are stimulants used to treat ADHD?

Stimulant medications are among the most commonly prescribed treatments for Attention Deficit Hyperactivity Disorder (ADHD) in Ireland.

These medications work by increasing levels of dopamine and norepinephrine in the brain, which help to improve focus, reduce impulsivity, and manage hyperactive behaviour.

ADHD medications are prescribed by specialists such as consultant psychiatrists or paediatricians, often following a referral from a GP. Treatment usually forms part of a broader care plan that may also include behavioural therapy, counselling, and educational support.

Common stimulants prescribed to treat ADHD include methylphenidate (e.g. Ritalin, Concerta XL), lisdexamfetamine (e.g. Elvanse), and dexamfetamine. These medications are controlled under the Misuse of Drugs Acts 1977 to 2016 and are only available on prescription.  

More information about ADHD can be found on this page:

• ADHD Ireland (support and resources for individuals and families): https://adhdireland.ie

Who should not take stimulant drugs?

Stimulants (uppers) should generally be avoided by people who:

• Have a history of heart problems such as irregular heartbeats, high blood pressure, or previous heart attacks
• Suffer from severe anxiety, panic disorders or bipolar disorder, as stimulants can worsen these conditions
• Have a history of substance misuse or addiction
• Suffer from sleep disorders such as insomnia
• Are taking medications that could dangerously interact with stimulants (e.g. certain antidepressants)
• Are pregnant or breastfeeding – stimulant use is generally not recommended unless explicitly advised by a medical professional

How do downers (depressant drugs) affect the central nervous system?

‘Downers’ or depressant drugs are substances that slow down activity in the central nervous system (CNS), causing a calming or sedative effect. They are commonly prescribed for conditions such as anxiety, sleep disorders and muscle spasms.

Depressants work by increasing the activity of a neurotransmitter called gamma-aminobutyric acid (GABA), which inhibits brain activity, promoting relaxation and reducing overactivity in the nervous system.

Common side-effects of downers include:

• Slower heart rate and breathing
• Reduced blood pressure
• A feeling of drowsiness or sedation
• Poor coordination and slowed reactions
• Confusion or memory problems (especially in high doses)

When used correctly under medical supervision, CNS depressants such as benzodiazepines or certain hypnotics can be effective for short-term relief. However, long-term use or misuse increases the risk of:

• Tolerance (needing more to feel the same effect)
• Dependence
• Withdrawal symptoms when stopping
• Life-threatening respiratory depression

Many depressant medications in Ireland are classified as controlled drugs under the Misuse of Drugs Acts 1977 to 2016, meaning they must be prescribed and dispensed with strict medical oversight due to their potential for misuse, dependence, and addiction.

What are common examples of downers/downer drugs?

Downer drugs include a wide range of substances that slow down activity in the central nervous system (CNS). Some are prescribed legally for medical use, while others are misused recreationally or obtained illegally. Many of these drugs fall under the Misuse of Drugs Acts 1977 to 2016, meaning they are controlled substances with restrictions around prescribing, possession, and supply.

Prescription medications

• Benzodiazepines – used short-term for anxiety, panic attacks or insomnia
  • Diazepam (Valium)
  • Lorazepam
  • Temazepam
• Hypnotics – used for short-term treatment of insomnia
  • Zopliclone
  • Zolpidem
  • Zaleplon
• Muscle relaxers – used to relieve muscle spasms or tension
  • Baclofen
  • Methocarbamol

Illicit or recreational depressants

• Alcohol – a widely used and more socially acceptable CNS depressant
• Gamma-hydroxybutyrate (GHB) – sometimes referred to as the ‘date rape drug’; can cause euphoria, sedation, and unconsciousness in high doses
• Opioids – opioids like heroin or prescription painkillers have strong CNS depressant effects and are often misused alongside other downers

Over-the-counter (OTC) sedatives

Some medications with sedative effects (e.g. certain antihistamines) are available without prescription but still pose risks when misused or combined with other substances. 

While many of these drugs can be safe and effective when used appropriately, combining multiple depressants or using them outside medical guidance significantly increases the risk of overdose and death.

If you’re concerned about your own or someone else’s drug use, confidential support is available through services such as your GP, the HSE Drug and Alcohol Helpline, and organisations like Drugs.ie.

What are the signs and symptoms of depressant use?

The signs and symptoms of depressant drugs or downers can range from mild sedation to dangerous levels of respiratory depression, depending on the drug and dosage.

Physical signs may include:

• Drowsiness or excessive sleepiness
• Slurred speech
• Poor coordination or unsteady movements
• Slow breathing or heart rate
• Dry mouth
• Drooping eyelids or lethargic appearance

Behavioural and psychological signs may include:

• Lack of motivation or slowed thinking
• Confusion or memory lapses
• Depressed mood
• Difficulty concentrating
• Irritability or emotional withdrawal
• Neglect of responsibilities

Signs of depressant overdose or serious misuse include:

• Shallow or dangerously slow breathing
• Loss of consciousness
• Cold or bluish skin (especially lips or fingertips)
• Unresponsiveness
• Seizures
• Coma or death (particularly when combined with alcohol or opioids)

Can mixing uppers and downers be dangerous?

Yes, mixing uppers (stimulants) and downers (depressants) can be extremely dangerous.

People sometimes combine these substances – intentionally or unintentionally – to “balance out” the effects of one drug with the other.

For example, someone might use cocaine (a stimulant) to stay awake while drinking alcohol (a depressant) or take benzodiazepines to come down from an MDMA high. However, this combination puts immense strain on the body and significantly increases the risk of serious health complications.

Some of the dangers of mixing uppers and downers include:

• Masking effects
  One drug can hide the signs of overdose from the other, leading people to take more than is safe. For example, stimulants may mask the sedative effects of alcohol, leading to alcohol poisoning without the usual warning signs.
• Increased risk of overdose
  Because the body is receiving mixed signals (e.g. being stimulated and sedated at the same time), it becomes harder to regulate basic functions like breathing, heart rate, and temperature – which can be life-threatening.
• Strain on the heart
  The opposing effects can place extra stress on the cardiovascular system, increasing the risk of heart attack, stroke, and irregular heartbeats, particularly when high doses are involved.
• Unpredictable psychological effects
  The combination of a stimulant’s euphoria and a depressant’s numbing effect can cause confusion, agitation, paranoia, or even psychotic episodes.

Common and risky combinations of uppers and downers include:

• Alcohol and cocaine 
  This combination produces a third toxic substance in the liver called cocaethylene, which is more harmful than either drug alone.
• Stimulants and benzodiazepines 
  Combining stimulants and benzodiazepines or ‘benzos’ can increase the risk of accidental overdose, especially if the sedative effects kick in after the stimulant wears off.
• Alcohol and opioids or GHB 
  This combination can cause respiratory depression and death.

If you are concerned about someone’s poly drug use (using different drugs together) or want support, you can speak with your GP, contact the HSE Drug and Alcohol Helpline, or visit Drugs.ie for advice, information, and details of local support services.

How can substance abuse involving uppers and downers be treated?

Substance misuse involving stimulants (uppers) or depressants (downers) can have serious physical and psychological effects, but support and treatments are available across Ireland.

Treatment typically begins with an assessment by a GP or local drug and alcohol service, followed by a personalised plan that may include:

• Detoxification (if physically dependent, especially on depressants like alcohol or benzodiazepines)
• Counselling or talking therapies, such as Cognitive Behavioural Therapy (CBT)
• Ongoing support from peer groups or community organisations
• Treatment for co-occurring conditions, like anxiety or ADHD, where appropriate

You can access help through your GP, HSE Drug and Alcohol Helpline, Drugs.ie, Ana Liffey Drug Project or other regional services.

How can I find out if a friend or family member is using uppers or downers?

Our ISO 17025-accredited laboratory can test for the widest range of substances, including uppers (stimulants) and downers (depressants).

Our easy-to-use, Home Urine Drug Test has been designed to give you peace of mind or enable you to seek support for a friend or loved one who has been abusing drugs.

We also offer court-admissible drug testing for legal and official matters using a variety of sample types including hair, nails, urine and oral fluid.

For confidential advice about which test might best suit your needs, call our Customer Services team on 01 402 9466 or email info@alphabiolabs.ie.