Opioid Addiction: The Causes, Symptoms and Side Effects
Opioid addiction is fast becoming one of Britain’s most serious, and often overlooked, public health crises. While much of the spotlight has been on the devastating opioid epidemic in North America, the UK is quietly facing its own surge in opioid misuse and drug-related deaths. Today, opioids are responsible for nearly half of all drug fatalities in this country, leaving a trail of heartbreak across families and communities.
To tackle this crisis, it’s essential to understand how opioid addiction develops, why it takes hold, and most importantly, that recovery is possible.
What is opioid addiction?
“Opioids” is the term used for a large group of drugs ranging from prescription pain medicines like hydrocodone or oxycodone, through to street drugs like heroin. You might sometimes hear them called “opiates,” which specifically refers to natural opioids made from the opium poppy, such as morphine. However, “opioids” also include synthetic drugs like fentanyl, made in labs to act in similar ways to natural opiates.
Opioids are so often prescribed because they’re incredibly good at managing pain. They bind to special receptors (opioid receptors) in your brain, making pain easier to handle and usually giving a sense of relaxation or even happiness.
Unfortunately, it is this same calming and comforting effect that can make opioids dangerously habit-forming. Opioid and opiate addiction develop when you keep using the drugs despite knowing they are causing real problems. Addiction can develop whether you initially got the drugs from your doctor or started using them illegally, with both equally dangerous.
Potentially addictive opioids include:
Buprenorphine
Buprenorphine is often used during opioid addiction treatment to help people stop taking stronger drugs. However, some people can start relying on buprenorphine itself, swapping one dependency for another.
Codeine
Codeine is found in various painkillers and even in some cough syrups. It might seem harmless because it is milder than other opioids, but if you take it too often or for too long, it can still lead to a codeine addiction.
Dihydrocodeine
Doctors prescribe dihydrocodeine for serious pain and sometimes breathing issues. However, it is a powerful drug designed to enhance the effects of codeine, and people can quickly become both physically and mentally dependent on it.
Fentanyl
Fentanyl is one of the strongest opioids out there and one of the most dangerous and addictive. It has caused a huge number of overdose deaths because just a tiny bit too much can be fatal.
Methadone
Methadone is supposed to support recovery from stronger opioids, but it isn’t risk-free. As with buprenorphine, some people find themselves relying on methadone instead, creating a new kind of dependency.
Morphine
Morphine is used in hospitals for serious pain, often after surgery. It has been trusted for centuries, but it’s so strong that misuse can quickly lead to a morphine addiction or overdose.
Oxycodone
Oxycodone is a very potent drug that has been at the centre of the opioid crisis in North America. While it was originally marketed as safe and non-addictive, we now know oxycodone can easily cause addiction and fatal overdoses.
Tramadol
Tramadol is used for moderate pain, but it’s still a dangerous opioid. If you start taking more tramadol than prescribed or keep using it when the pain is gone, tramadol addiction can sneak up fast.
Vicodin
Vicodin combines hydrocodone with paracetamol. It is very strong and, without careful medical oversight, it can become a seriously addictive drug.
How do opioid and opiate addiction develop?
Opioids and opiates interact powerfully with your brain’s reward system by releasing dopamine, a chemical that naturally makes you feel pleasure. This release can initially feel great, and along with the pain-relief effects, can encourage you to use the drugs again to relive those feelings.
However, the more you use opioids or opiates, the more your brain adjusts by producing less dopamine on its own. Eventually, normal things that used to bring happiness or comfort stop feeling good without opioids. This is called developing a “tolerance”, and it means you need higher doses of the drugs to feel close to the original effects.
Tolerance often quickly turns into a physical opiate dependency, meaning your body relies on opioids to function normally. If you try to stop taking the drugs, especially going “cold turkey” and quitting suddenly, you will be impacted by severe withdrawal symptoms, which can trigger a relapse. Opioids can also become a coping mechanism, a kind of emotional crutch you use to handle stress, trauma or sadness, deepening addiction even further.
Your risk of developing an opioid addiction also depends on a number of personal factors, such as:
- Genetics and family history of addiction
- Chronic physical pain or mental health problems leading to prolonged opioid abuse
- How easily you can access opioid medications
- Running out of prescription drugs and using street drugs to replace them
- The types of opioids you use and how you use them
- The environment you grew up in
- Living with high levels of stress
All of these will need addressing and resolving during opioid detox and rehab.
What are the telltale opioid addiction signs and symptoms?
Opioid addiction doesn’t always look obvious from the outside, especially if you started using opioids for legitimate pain relief. But noticing these symptoms of drug addiction early and getting help right away can save your life:
- Hiding your activities or whereabouts to cover opioid use
- Sudden financial troubles or secrecy about spending
- Pulling away from family and friends to avoid difficult conversations
- Feeling irritable, uncomfortable or anxious when opioids wear off
- Being unusually sleepy, drowsy or falling asleep during normal activities
- Extremely small pupils
- Needle marks or bruises if you inject opioids
If you spot any of these symptoms of drug addiction, professional opioid rehab and detox can help prevent a fatal disaster.
Reach out to our expert support team 24 hours a day
Start the Opiate Rehabilitation Process Today
Finding the best opiate treatment is vital for long-term recovery success. Our friendly and compassionate team will hold your hand through the process until you learn to love yourself again.
Opioid addiction UK factsheet
- 137,965 adults received rehab treatment for opiate and opioid addiction between April 2023 and March 2024. This made up 44% of all substance misuse treatments and was the largest single group in treatment services.
- In 2023, 2,551 drug-poisoning deaths involved opioids or opiates. This was an increase of 12.8% from 2,261 deaths in 2022 and accounted for nearly half of all drug-poisoning fatalities.
- Roughly 72% of adults entering opioid addiction treatment (115,229 people) reported co-existing mental health issues.
- A rise in deaths linked to potent synthetic opioids, including nitazenes, has been reported in recent years. In England alone, 179 confirmed nitazene-related deaths occurred from June 2023 to May 2024.
What are the most dangerous opioid side effects and addiction risks?
Opioid addiction is dangerous and even life-threatening, even when you’re taking prescribed medications. Here are some of the biggest risks to be aware of:
Opioid overdose
This is the most immediate and serious danger. Overdoses can happen when you take higher doses, mix opioids with alcohol or other depressants or use stronger versions like fentanyl. Signs of an opioid overdose include:
- Not waking up or responding
- Breathing that’s slow or shallow
- Tiny, pinpoint pupils
- Cold or clammy skin
- Your body going limp
- Choking or strange gurgling noises
- Your heartbeat slowing down or becoming irregular
If you see any of these signs, call emergency services right away.
Mental health struggles
Anxiety, depression and PTSD symptoms often get worse with opioid addiction and in some cases, it can also trigger new mental health problems.
Infections from needle use
Sharing needles can pass on HIV, hepatitis C and other serious illnesses.
Infections from needle use
Sharing needles can pass on HIV, hepatitis C and other serious illnesses.
Breathing issues
Opioids can slow your breathing so much that your brain doesn’t get enough oxygen. This can cause permanent brain damage or death.
Constipation and gut problems
Long-term opioid abuse is notorious for causing severe digestive issues.
Heart complications
Injecting opioids can damage your heart or lead to infections, heart attacks or even strokes.
Finding help if you have an opioid addiction
At Providence Projects, we understand how hard it is to admit you need help and even harder to ask for it. That’s why in our primary treatment offerings, we offer a gentle, structured opioid detox as a part of our prescription drug rehab treatment, in a supportive and understanding setting. You’ll get access to a wide range of rehab therapies, that you can continue to benefit from through our optional secondary care, and due to our carefully designed treatment pathway, that care doesn’t stop the moment you walk out the door, thanks to offerings like our sober living and management plans, and our UKAT Alumni Programme.
Contact us whenever you’re ready to make a change.
Reach out to our expert support team 24 hours a day
Start the Opiate Rehabilitation Process Today
Finding the best Opiate addiction treatment is vital for long-term recovery success. Our friendly and compassionate team will hold your hand through the process until you learn to love yourself again.
Frequently Asked Questions
How to prevent an opioid addiction?
If you are given opioids for pain, try to take the lowest effective dose for the shortest time possible and always follow your doctor’s instructions closely. Be honest about any history of mental health struggles, addiction or trauma, as they may suggest different pain relief that’s safer for you. If you notice yourself starting to rely on the pills emotionally or feel uneasy when you don’t take them, speak up early.
How is opioid addiction screened?
Opioid addiction is often picked up through basic screening tools that ask about your usage patterns, mental health and how opioids fit into your life. These might include questions like: Are you taking more than the prescribed amount? Do you feel anxious without them? Are they affecting your work or relationships? This screening can be conducted through your GP, a drug support service, or a rehabilitation centre, such as the Providence Projects.
Are there safe alternatives to opioids for pain management?
Absolutely. Depending on what’s causing your pain, treatments like heat therapy, gentle movement, massage, non-opioid medications or talking therapies can help you feel better without risking addiction. In many cases, a combination of physical and mental health support can make a big difference. There is no one-size-fits-all solution, so talk to your doctor about building a long-term pain plan that doesn’t rely on opioids.
(Click here to see works cited)
- UK Rehab. “Opioid Addiction | Causes, Symptoms and Diagnosis.” UK Rehab, https://www.uk-rehab.com/prescription-drug-addiction/opioid/ – Accessed 11 July 2025.
- NCBI. “Opioid Use Disorder – StatPearls.” NCBI, 17 January 2024, https://www.ncbi.nlm.nih.gov/books/NBK553166/ – Accessed 11 July 2025.
- World Health Organization (WHO). “Opioid overdose.” World Health Organization (WHO), 29 August 2023, https://www.who.int/news-room/fact-sheets/detail/opioid-overdose – Accessed 11 July 2025.
- Friebel, Rocco, and Laia Maynou. “Trends and characteristics of hospitalisations from the harmful use of opioids in England between 2008 and 2018: Population-based retrospective cohort study.” Journal of the Royal Society of Medicine vol. 115,5 (2022): 173-185. doi:10.1177/01410768221077360
- Office for National Statistics. “ONS: Deaths related to drug poisoning in England and Wales: 2023 registrations.” Deaths related to drug poisoning in England and Wales – Office for National Statistics, 23 October 2024, https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/deathsrelatedtodrugpoisoninginenglandandwales/2023registrations – Accessed 11 July 2025.
- GOV.UK. “Adult substance misuse treatment statistics 2023 to 2024: report.” GOV.UK, 28 November 2024, https://www.gov.uk/government/statistics/substance-misuse-treatment-for-adults-statistics-2023-to-2024/adult-substance-misuse-treatment-statistics-2023-to-2024-report – Accessed 11 July 2025.
- GOV.UK. “Deaths linked to potent synthetic opioids.” GOV.UK, 3 October 2024, https://www.gov.uk/government/publications/deaths-linked-to-potent-synthetic-opioids/deaths-linked-to-potent-synthetic-opioids Accessed 11 July 2025.