Last Updated:

January 30th, 2026

Codeine addiction: Signs, symptoms and side-effects

Codeine stands apart from other opioids in one important way: it’s easily accessible. You can walk into a pharmacy like Boots and buy a low-dose version combined with paracetamol or ibuprofen. While higher-strength codeine requires a GP prescription, it remains one of the most widely prescribed opioids in the UK. What many people don’t realise, however, is that codeine is powerful, potentially dangerous, and highly addictive. Recognising the signs of dependence and understanding the risks is essential for safe and responsible use.

Codeine addiction tablets in bottle

What is codeine addiction?

Codeine addiction is when you keep using even though it’s hurting your health, your relationships, or the way you live day-to-day. Codeine turns into morphine once it’s in your body, works on the same brain receptors as heroin and other opioids, and creates the same physical dependence.

The problem with codeine is that, because you can buy it from the chemist for a toothache or a cough, it doesn’t feel like a dangerous drug. But when withdrawal hits, if you are dealing with emotional or mental struggles too, a full and dangerous opioid addiction can take hold.

How does codeine addiction develop?

Codeine addiction usually starts with real pain, but can also develop through recreational or self-medicating codeine misuse. Here are the three main stages of how it typically progresses:

Codeine abuse
No matter why you started taking codeine, it can make you feel peaceful, calm, and sedated. That feeling becomes something you look forward to, even if you don’t medically need codeine anymore. You may then start taking it for smaller discomforts, “just in case” pain starts up again, or “microdose” throughout the day to keep up a low-level buzz.
Codeine dependence
Codeine dependence means your brain believes it needs codeine just to keep running. If you stop, withdrawal hits you with symptoms ranging from headaches to sweating to crippling anxiety. This is when you have to keep a steady supply of codeine coming, so you start seeing multiple doctors, or working out which chemists don’t ask questions.
Codeine addiction
Physical dependence can then become full addiction when you can’t stop using codeine, even when you want to. Once you have reached this point, every thought circles back to codeine, whether you have enough, how to get more, and the fear of running out.

Recognising codeine addiction signs

Codeine addiction is easy to miss because there is often no obvious moment when things go wrong. Especially if you were originally prescribed codeine, addiction denial is a natural reaction to growing issues. But if you are starting to worry, watch for these codeine addiction signs:

  • Buying codeine daily or making sure you never run out.
  • Getting codeine withdrawal symptoms when you go too long without taking any.
  • Taking codeine even when you don’t have pain, just to feel okay.
  • Spending money you don’t really have on codeine.
  • Trying and failing to cut down on how much codeine you’re taking.
  • Stomach problems, nausea, liver pain from all the paracetamol or ibuprofen in combination products.
  • Lying to friends and family about what’s really going on.

man with Codeine tablet dust

Why is codeine addictive?

Codeine is a prodrug, which means your liver converts it into morphine, which then attaches to opioid receptors in your brain. This triggers a dopamine release and creates feelings of warmth and well-being alongside the pain relief. Your brain adapts quickly, making less of its own natural painkillers and locking you into physical dependence.

But for a true emotional or mental codeine addiction to develop, certain other factors are also important to understand:

Codeine addiction and mental health
Codeine can take the edge off when you’re anxious, depressed, stressed, or haunted by traumatic memories. That mental and emotional calming can be just as real as physical pain relief, and codeine can become an easy daily fix.
Chronic pain with limited options
If you are living with ongoing pain and codeine is what gets you through the day, stopping can feel both impossible and illogical. If you feel like there is no other solution, the fear of pain returning keeps you taking it even when you know you’re dependent.
Genetic factors
Some people are “ultra-rapid metabolisers”, which means their bodies convert codeine to morphine much faster than average. This is a genetic thing passed down from your parents, and it creates stronger effects and a higher addiction risk.
Easy access
At a time when it has never been harder to get a GP’s appointment in Britain, codeine is one of the most easily available painkillers beyond paracetamol or ibuprofen. All you need to do is walk into a chemist and buy it, and you can start taking it without any medical oversight at all.

Codeine side effects and addiction dangers

Codeine misuse is far more dangerous than most people think, and it can and does kill people every year. Some of the dangers that everyone using codeine needs to know include:

Codeine overdose
Like all opioids, codeine slows your breathing and high doses or those combined with alcohol or sedatives can stop your breathing altogether. There were 242 deaths by codeine poisoning in 2023, the highest ever, often involving people who didn’t realise over-the-counter medication could be lethal.
Overdose from combination medications
Most over-the-counter codeine is mixed with paracetamol or ibuprofen, so overusing it means overdosing on those too. Paracetamol can cause fatal liver failure, while ibuprofen overuse can lead to ulcers, bleeding, and kidney damage. Some try cold water extraction to separate codeine, but it’s risky, unreliable, and still dangerous.
Mental health and cognitive effects
Long-term codeine misuse can create or worsen mental health issues like anxiety and depression, and affect everything from memory to concentration. These effects can persist after stopping, though they usually improve with time.
Severe constipation
Codeine slows your digestive system dramatically, causing chronic constipation that can cause serious health issues and become a medical emergency.

What does codeine addiction recovery involve?

Codeine addiction recovery needs proper support because the withdrawal is hard, and the psychological side can run very deep. Inpatient codeine rehab programmes are generally considered the most effective, with three stages needed for lasting recovery:

1. Prescription drug detox

A professionally planned and delivered drug detox gets you through withdrawal safely. It is much safer than a home detox as you will taper down gradually, switch to substitute medication if necessary, and get the necessary physical and psychological support.

2. Opioid rehab

Drug rehab therapy then helps you understand and change your relationship with codeine, addresses any underlying pain issues with non-opioid alternatives, and teaches relapse prevention strategies and coping skills.

3. Support for post-rehab recovery

This may include further therapy, either privately sought or provided by your rehab centre, local support like NA meetings, and pain management therapy.

If you or someone you know is struggling with codeine addiction, you don’t have to face it alone. Contact us today for expert advice on the best path to recovery.

Frequently Asked Questions

Can codeine addiction develop without heavy daily use?
Yes, you don’t need to take codeine every day to become addicted. Some people use it a few times a week whenever pain flares up, or when they’re feeling stressed and still develop addiction. The pattern and why you are taking it often matter more than how often or even how much you are taking.
Can codeine lead to addiction even when taken as prescribed?
Yes, following your prescription doesn’t protect you from addiction. Your body doesn’t know the difference between “prescribed” and “not prescribed”; it just knows you’re taking an opioid regularly. Physical dependence can develop within weeks, even at normal doses, and many people become addicted while doing exactly what their doctor told them to do.
How does codeine affect decision-making and impulse control?
Long-term codeine use affects your judgement and self-control. You may spend money you don’t have, lie to loved ones, or take risks you’d normally avoid. The drug hijacks your brain’s reward system, making codeine feel more important than anything else.

(Click here to see works cited)