A lot of people don’t think of codeine as a drug with serious risks. It gets prescribed regularly, it comes in combination medications, and it doesn’t carry the same stigma as other opioids. So when use becomes a problem, it can take a while to recognize. The effects of long-term codeine use are worth understanding, not because the picture is bleak, but because knowing what’s happening in your body makes it easier to make sense of what you’re going through.
What Codeine Does in the Body
Codeine works by converting to morphine in the liver after you take it. That’s actually where most of the pain relief comes from. It also slows the nervous system, which is why it can create that drowsy, calm feeling, and for some people, that feeling becomes something they start to depend on without fully realizing it. The drug doesn’t announce itself as addictive. It just starts to feel necessary.
The body adjusts to codeine faster than most people expect. With regular use, it starts to need the drug just to feel normal, not to feel good, but simply to avoid feeling sick. At that point, a person isn’t really in control of how much they’re taking or how often they’re taking it. The shift from use to dependence can happen gradually, which is part of what makes it so easy to miss.
Codeine also interacts with the brain’s reward system by triggering a release of dopamine. Over time, the brain begins to rely on it to produce that response, which makes stopping feel far more difficult than it should. It’s worth understanding that this isn’t a personal failure. It’s a neurological process that happens to many people who take opioids regularly.
The Side Effects of Long-Term Codeine Use
The side effects of long-term codeine use span nearly every system in the body. Some are uncomfortable. Others are genuinely dangerous. Most don’t appear right away, which is why people are often surprised by how much has changed after months or years of regular use.
Digestive issues are one of the first things people notice with regular codeine use. Constipation is common and tends to get worse the longer someone uses it. Beyond that, cramping, nausea, and bowel dysfunction can develop and become persistent problems. When codeine is taken in a combination product that also contains acetaminophen, the liver is put under extra strain. Those formulas are harder on the body than people often realize, and extended use can lead to liver damage that builds quietly over time.
Getting decent sleep becomes difficult for many people who use codeine regularly. Waking up through the night, vivid nightmares, and that groggy feeling, regardless of how many hours you sleep, are all pretty common complaints. What’s harder to connect to codeine use is the mood piece. People often describe feeling flat, short-tempered, or emotionally checked out when they haven’t used recently, and that discomfort can quietly push them toward using again just to feel okay. It doesn’t feel like addiction from the inside. It just feels like needing to feel normal.
Here’s something that surprises a lot of people: codeine can actually make pain worse over time. With extended use, the nervous system becomes more sensitive rather than less, a process called opioid-induced hyperalgesia. So someone might find themselves in more pain than before they ever started taking it, which drives them to take more to get relief. It’s a difficult cycle to be in. For those already caught in it, opioid addiction treatment can help untangle both the physical patterns and the psychological ones.
Can You Be Addicted to Codeine?
A question people ask, sometimes quietly and sometimes out loud, is whether you can be addicted to codeine. The answer is yes, and it happens more often than most people realize. According to the 2024 National Survey on Drug Use and Health, 2.0 million people aged 12 and older misused codeine products in the past year. That figure represents roughly 1 in 4 of the 7.6 million people who misused prescription opioids overall — a reminder that codeine is far from a low-risk medication.
Most people picture addiction as someone taking large quantities of a drug. The reality is usually quieter than that. It might look like reaching for codeine before getting out of bed, or feeling a low-grade anxiety start to build when a prescription is almost gone. It might be taking a little more than prescribed because the usual amount stopped working. Noticing those patterns matters, even when the prescription came from a doctor. Codeine addiction treatment can help someone work through both the physical side of dependence and the habits that have quietly built up around it.
How Long-Term Codeine Use Affects Daily Life
Codeine use doesn’t only affect the body. Over time, it tends to affect everything around a person as well. Relationships are often where the strain shows up first, sometimes before the person using has fully acknowledged there’s a problem. A partner or family member may notice the irritability, the withdrawal, the unreliability, and not know how to name what they’re seeing. That disconnect adds its own weight to an already hard situation.
Staying on top of work gets harder when so much energy goes toward managing codeine use. Missed deadlines, more sick days, trouble concentrating — these things tend to accumulate before someone connects them to their codeine use. Money becomes an issue, too, especially when someone is sourcing the drug outside of a prescription. The financial and professional pieces of this often quietly unravel alongside everything else.
One of the most serious risks associated with long-term opioid use is overdose. Respiratory failure is the leading cause of death from opioid addiction, according to the National Institute on Drug Abuse. When someone has built up a tolerance and then takes a higher dose, or mixes codeine with alcohol or other substances, the risk rises sharply. Non-fatal overdoses also carry lasting consequences, including brain injury from oxygen deprivation.
Long-Term Side Effects of Codeine on Mental Health
Mental health is one of the areas where long-term codeine use does some of its quieter damage. The connection isn’t always obvious at first. Someone might notice they feel more anxious than usual, or that they’ve lost interest in things that used to matter to them. By the time those changes feel significant, the drug has often been reshaping brain chemistry for months.
Depression is common with extended opioid use, and it goes deeper than just feeling down. The brain’s ability to regulate mood becomes genuinely disrupted, making it harder to feel motivated, hopeful, or even okay on an ordinary day. Anxiety tends to run alongside it, especially in the hours between doses or when access to codeine becomes uncertain. People sometimes describe it as a low hum of dread that’s hard to pin on anything specific, which makes it easy to dismiss or chalk up to stress.
Thinking clearly becomes harder, too. Memory slips, focus drifts, and decisions that used to feel straightforward start to take more effort. For someone trying to hold down a job or show up for their family, that cognitive fog is frustrating in ways that are difficult to explain to others. The good news is that many of these symptoms do ease after stopping. Medication-assisted treatment (MAT) can help stabilize both the physical withdrawal and the mood disruption that make early recovery so difficult to push through on willpower alone.
Overcome the Effects of Long-Term Codeine Use Today
If you’ve been reading this and recognizing yourself, or someone you love, know that the effects of long-term codeine use are serious, but they don’t have to define what comes next. At Enlightened Recovery Michigan, we work with people who are navigating opioid dependence in all its forms. Our approach addresses both the medical realities of withdrawal and the emotional weight that comes with it, so nothing gets left behind. Whether you’re just starting to question your codeine use or you’ve been struggling for a long time, our team is here to talk through your options honestly and without judgment. Contact us today to learn more about how we can help you or a loved one move forward.