Understanding Overdose: Risks, Signs and How to Prevent Drug and Alcohol-Related Harm

Understanding the risks, recognising the warning signs and knowing how to respond can help save lives.

Inspire provides specialist overdose awareness and prevention and practical harm reduction support to help people stay safer.

What Is an Overdose?

An overdose occurs when a drug, alcohol or medication overwhelms the body's ability to function normally.

Different substances affect the body in different ways. Some slow down breathing, heart rate and brain activity, while others overstimulate the heart, nervous system and brain. Both can lead to serious medical emergencies and, in some cases, death.

An overdose can happen to:

• People who use substances regularly
• First-time users
• People taking prescribed medicines
• People returning to use after a period of abstinence
• Anyone using substances that contain unexpected or unknown ingredients

The risk of overdose can affect anyone, which is why awareness, education and access to support are so important.

The Growing Impact of Overdose in the UK

Drug and alcohol-related deaths remain a significant public health challenge across the UK. Recent figures show that overdose deaths continue to rise, highlighting the importance of awareness, harm reduction and access to support services.

Key Statistics

• In England and Wales, 5,565 deaths related to drug poisoning were registered in 2024, the highest number on record and an increase from 5,448 in 2023.
• The rate of drug poisoning deaths has more than doubled since 2012.
• Almost half of all drug poisoning deaths registered in 2024 involved an opioid or opiate.
• Deaths involving cocaine continue to rise sharply.
• Men account for around two-thirds of drug poisoning deaths.
• People aged 40 to 49 experience some of the highest rates of drug-related deaths.
• Emerging synthetic opioids such as nitazenes are causing increasing concern.

These figures demonstrate why overdose awareness, naloxone provision and harm reduction services continue to play an important role in reducing preventable deaths.

An Evolving Drug Landscape

Overdose risks are changing.

Alongside longstanding concerns around heroin and other opioids, services are increasingly seeing risks associated with:

• Cocaine and crack cocaine
• Synthetic opioids such as nitazenes
• Prescription medicines including pregabalin and benzodiazepines
• Polydrug use (using multiple substances together)
• Alcohol combined with other drugs

Many drug-related deaths now involve more than one substance, making education around mixing drugs and alcohol an essential part of overdose prevention.

What Increases the Risk of Overdose?

Several factors can increase the likelihood of an overdose.

Common Risk Factors

• Mixing drugs and alcohol
• Using alone
• Taking larger amounts than usual
• Reduced tolerance following a period of abstinence
• Using drugs with unknown strength or contents
• Physical health conditions
• Mental health difficulties
• Using multiple substances at the same time

Many drug-related deaths involve more than one substance, highlighting the importance of understanding how drugs interact with each other.

It is also important to remember that prescribed medicines can cause overdose if they are taken in larger quantities than prescribed or combined with alcohol, illicit substances or other medications.

Harm reduction advice can help reduce these risks. Inspire provides harm reduction support, including safer use advice, overdose prevention information, needle and syringe programmes and access to naloxone.

Opioid Overdose

Opioids are among the substances most commonly associated with fatal overdose.

Common Opioids

• Heroin
• Fentanyl
• Nitazenes
• Morphine
• Oxycodone
• Methadone
• Codeine
• Tramadol

Opioids reduce pain by slowing activity within the central nervous system. In high doses, they can suppress breathing to dangerous levels.

Know the Five Signs of an Opioid Overdose

Without urgent intervention, an opioid overdose can become fatal.

What To Do If Someone Is Experiencing an Opioid Overdose

If you suspect someone is overdosing on opioids:

1. Call 999 immediately.
2. Administer naloxone if it is available.
3. Place the person in the recovery position if they are unconscious but breathing.
4. Stay with them until emergency services arrive.
5. If they stop breathing and you are trained to do so, begin CPR and follow instructions from the emergency call handler.

Always seek emergency medical help, even if naloxone appears to work.

Stimulant Overdose

Stimulants speed up the body's systems and can place significant strain on the heart, brain and nervous system.

Common Stimulants

• Cocaine
• Crack cocaine
• Amphetamine
• Methamphetamine
• MDMA (Ecstasy)

Stimulant overdose is sometimes referred to as "overamping".

Unlike opioid overdoses, which are characterised by sedation and respiratory depression, stimulant overdose is associated with overstimulation of the body's systems.

Signs of a Stimulant Overdose

Symptoms may include:

• Rapid heartbeat
• Chest pain
• Difficulty breathing
• Severe anxiety or panic
• Agitation
• Paranoia
• Confusion or disorientation
• High body temperature
• Hot, flushed or sweaty skin
• Seizures
• Collapse or loss of consciousness

Stimulant overdoses can result in stroke, heart attack or cardiac arrest and should always be treated as medical emergencies.

How To Respond to a Stimulant Overdose

If someone is experiencing a stimulant overdose:

1. Call 999 immediately if they have chest pain, breathing difficulties, seizures, collapse, loss of consciousness or you have serious concerns about their condition.
2. Move them to a calm, quiet environment away from crowds, noise and bright lights where possible.
3. Help keep them cool if they are overheating.
4. Reassure them and remain calm.
5. Encourage slow, controlled breathing if they appear panicked.
6. Do not give alcohol or other substances to counteract the effects.
7. If they have a seizure, protect them from injury and do not place anything in their mouth.
8. If unconscious but breathing, place them in the recovery position.
9. If they stop breathing and you are trained, begin CPR and follow emergency call handler instructions.

Remember: stimulant overdoses can become life-threatening very quickly and should always be treated as medical emergencies.

Cocaine Overdose

Cocaine is one of the most commonly used stimulant drugs and can have serious effects on the cardiovascular system.

Many people underestimate the risks associated with cocaine use, particularly in social settings.

Because cocaine increases heart rate and constricts blood vessels, overdose can be associated with:

• Heart attack
• Stroke
• Seizures
• Dangerous heart rhythms
• Overheating
• Sudden cardiac arrest

The risks increase significantly when cocaine is used alongside alcohol.

What Is Cocaethylene?

When cocaine and alcohol are used together, the liver produces a toxic substance called cocaethylene.

Cocaethylene remains in the body for longer than cocaine alone and places additional strain on the heart, liver and other organs.

The combination can:

• Increase heart rate and blood pressure
• Increase the risk of heart attack
• Increase the risk of stroke
• Increase the risk of seizures
• Increase the risk of dangerous heart rhythms
• Increase the risk of sudden cardiac arrest

For this reason, it is safest to avoid mixing cocaine and alcohol.

How To Respond to a Cocaine Overdose

Cocaine overdose is a medical emergency.

If someone may be experiencing a cocaine overdose:

1. Call 999 immediately.
2. Keep them calm and provide reassurance.
3. Move them to a cool, quiet environment.
4. Help reduce their body temperature if they are overheating.
5. Encourage them to rest and avoid physical exertion.
6. Do not give alcohol, drugs or medication unless instructed by a healthcare professional.
7. Treat chest pain as a possible heart attack.
8. If they have a seizure, protect them from injury.
9. If unconscious but breathing, place them in the recovery position.
10. If they stop breathing and you are trained, begin CPR and follow emergency service instructions.

Important: The risk of serious complications is significantly higher when cocaine is used alongside alcohol due to the production of cocaethylene. If possible, tell emergency services what substances may have been taken.

Alcohol Overdose (Alcohol Poisoning)

Because alcohol is legal and widely available, its risks are often underestimated.

However, consuming large amounts of alcohol in a short period can overwhelm the body's vital functions, suppress breathing and lead to a potentially fatal overdose known as alcohol poisoning.

Signs of Alcohol Poisoning

Watch for:

• Vomiting
• Loss of coordination
• Slow or irregular breathing
• Pale, blue or grey-tinged skin
• Low body temperature
• Cold, clammy skin
• Seizures
• Loss of consciousness

Alcohol poisoning is a medical emergency and requires immediate attention.

How To Respond to Alcohol Poisoning

If you think someone has consumed too much alcohol, it is always safest to seek medical help.

1. Call 999 immediately if they are unconscious, difficult to wake, having a seizure or breathing very slowly.
2. Stay with them at all times.
3. If they are unconscious but breathing, place them in the recovery position.
4. Monitor their breathing closely.
5. If they vomit, help them sit up or roll onto their side.
6. Keep them warm and comfortable.
7. Do not give them coffee, energy drinks, food or a cold shower.
8. Do not encourage them to walk around if they are confused or struggling to stay awake.
9. If they stop breathing and you are trained, begin CPR and follow guidance from the emergency call handler.

Remember: Slow breathing, unconsciousness, seizures, repeated vomiting and difficulty waking someone are all signs of a potentially life-threatening alcohol overdose. Call 999 immediately.

What Is a Depressant Overdose?

Benzodiazepines and gabapentinoids are medicines that depress, or slow down, the central nervous system.

They are commonly prescribed for conditions such as anxiety, insomnia, epilepsy and nerve pain.

Common Benzodiazepines

• Diazepam
• Temazepam
• Lorazepam
• Alprazolam

Common Gabapentinoids

• Pregabalin
• Gabapentin

The risk of overdose increases significantly when these medicines are mixed with other depressants.

High-Risk Combinations

• Opioids
• Alcohol
• Benzodiazepines
• Sleeping tablets
• Other sedatives

These combinations can dramatically increase sedation and slow breathing to dangerous levels.

Signs of a Depressant Overdose

Common warning signs include:

• Extreme drowsiness
• Slurred speech
• Poor coordination
• Confusion
• Difficulty staying awake
• Unresponsiveness
• Reduced consciousness
• Slow, shallow or difficult breathing

A depressant overdose becomes particularly dangerous when breathing slows or stops.

How To Respond to a Depressant Overdose

1. Call 999 immediately if the person is difficult to wake, unresponsive or breathing slowly.
2. Try to wake them by calling their name or gently shaking their shoulders.
3. Check their breathing carefully.
4. Place them in the recovery position if they are unconscious but breathing.
5. Stay with them until emergency help arrives.
6. Do not leave them alone to "sleep it off".
7. Do not give them food, alcohol or other substances.
8. If opioids may also be involved, administer naloxone if available.
9. If they stop breathing and you are trained, begin CPR and follow emergency service instructions.

Remember: Slow, shallow or stopped breathing is the most serious sign of a depressant overdose and should always be treated as a medical emergency.

New Psychoactive Substances and Overdose

What Are New Psychoactive Substances?

New Psychoactive Substances (NPS), sometimes called "designer drugs", are synthetic substances designed to mimic traditional drugs.

Examples include:

• Synthetic cannabinoids (often called Spice)
• Synthetic stimulants
• Synthetic opioids

The biggest danger associated with NPS is unpredictability.

Strength, ingredients and effects can vary significantly between batches, making it difficult to know exactly what has been consumed and increasing the risk of overdose.

How To Respond to an NPS Overdose

Because NPS can contain a wide range of unknown ingredients, symptoms can vary significantly.

Always treat an NPS overdose as a medical emergency.

1. Call 999 immediately.
2. Try to identify what may have been taken and share this information with emergency services.
3. Monitor breathing and responsiveness.
4. Place the person in the recovery position if unconscious but breathing.
5. Administer naloxone if opioid contamination is suspected and naloxone is available.
6. Move them to a safe environment if they are agitated or distressed.
7. Help cool them down if they are overheating.
8. Protect them from injury if they are having a seizure.
9. Do not give alcohol, medication or other substances.
10. Begin CPR if they stop breathing and you are trained to do so.

Because it is often impossible to know what an NPS contains, medical assistance should always be sought immediately.

Why Mixing Drugs is Especially Dangerous

Many overdoses involve more than one substance.

Even when amounts may normally be tolerated individually, combining substances can produce unpredictable and potentially fatal effects.

Opioids and Alcohol

Both substances suppress breathing and can significantly increase the risk of respiratory failure.

Opioids and Benzodiazepines

This is one of the highest-risk drug combinations and is associated with profound sedation, breathing difficulties and fatal overdose.

Cocaine and Alcohol

When cocaine and alcohol are used together, the body produces cocaethylene, increasing strain on the heart and raising overdose risk.

Multiple Depressants

Using several substances that slow the central nervous system can make breathing dangerously slow or stop altogether.

For more information about how different substances interact, visit the Drugs & Me Drug Interaction Checker.

This interactive tool provides information about potential interactions between alcohol, cannabis, ketamine, MDMA and many other substances.

How to Reduce the Risk of Overdose

While no substance use is completely risk-free, harm reduction measures can reduce the likelihood of overdose and other serious health complications.

Harm reduction focuses on practical steps that help keep people safer and reduce drug-related harm.

Learn more about Inspire's harm reduction advice.

Practical Harm Reduction Tips

• Avoid mixing drugs and alcohol.
• Start with a small amount if using a new or unfamiliar substance.
• Avoid using alone where possible.
• Create a safety plan if you are using alone.
• Carry naloxone if opioids may be involved.
• Learn the signs of overdose.
• Test substances before use where possible through services such as WEDINOS.
• Seek medical attention immediately if someone becomes unwell.
• Keep communication open with trusted friends and support networks.
• Access specialist support when needed.

Small steps can make a significant difference in preventing serious harm.

Key Takeaways About Overdose

Overdose is not limited to one drug or one group of people.

Opioids, stimulants, alcohol, prescription medicines and combinations of substances can all lead to serious harm or death.

Understanding the risks, recognising the warning signs and knowing how to respond can help prevent avoidable deaths and keep people safer.

Whether you're looking for information, practical harm reduction advice or support for yourself or someone else, help is available.

Get Support

If you're concerned about your own substance use, worried about someone else, or looking for practical advice on staying safer, support is available.

Inspire provides:

• Drug and alcohol treatment services
• Harm reduction advice
• Recovery support
• Family support
• Mental health support
• Naloxone training and supply

Whether you are worried about your own substance use or concerned about someone else, help is available.