Looking into the impact codeine has on sleep

Codeine–one of the most widely recognised and abused opioids–is regularly prescribed for managing pain and suppressing cough. As a low-to-moderate strength opioid, codeine is highly valued for how accessible it is as well as its ability to relieve mild to moderate pain and ease coughing, notably in instances where over-the-counter solutions aren’t sufficient. Its effectiveness stems from its conversion to morphine in the liver, which then binds to opioid receptors in the brain, reducing the sensation of pain and creating a mild sedative effect that can promote rest in those experiencing discomfort.

Yet, despite its benefits, codeine comes with serious risks, especially when used over long periods or at higher doses. The use of codeine can lead to tolerance and dependence, with some individuals finding themselves increasingly reliant on the drug to manage both pain and withdrawal symptoms. Over time, codeine’s influence on the central nervous system can interfere with sleep quality, contributing to a range of sleep issues, including fragmented sleep, increased risk of sleep apnea, and, eventually, a dependency cycle where sleep quality worsens without the drug.

This article explores codeine’s impact on sleep, exploring its potential benefits, such as pain relief that may indirectly support better sleep, as well as its risks, including sleep disturbances and the potential for dependence.

The Importance of sleep

Sleep is very important for maintaining both physical and mental health, impacting nearly every system in the body. Physically, sleep enables the body to repair muscles, consolidate immune responses, and regulate metabolic functions. Mentally, it supports memory consolidation, enabling the brain to process and organise information from the day into long-term memory. Quality sleep is also critical for emotional regulation and cognitive functioning, including attention and problem-solving abilities.

When sleep quality is compromised, individuals may experience a range of health consequences. Poor or inconsistent sleep can lead to mood disorders such as:

• Anxiety and depression
• Reduced cognitive performance
• Diminished immune function

Chronic sleep deprivation has been linked to an increased risk of cardiovascular disease, obesity, and diabetes.

Common sleep disorders include:

• Insomnia, which makes it difficult to fall or stay asleep
• Sleep apnea, where breathing repeatedly stops and starts, disrupting restful sleep
• Restless leg syndrome (RLS), which causes discomfort and a strong urge to move the legs, particularly at night

Opioids like codeine, while initially sedative, often worsen these conditions by affecting the central nervous system and respiratory function, exacerbating issues like sleep apnea and disrupting sleep architecture, leading to fragmented sleep cycles.

How codeine affects sleep

Prolonged or frequent codeine use often leads to significant disruptions in the natural sleep cycle, particularly by altering essential sleep stages like REM and deep sleep.

One of the main ways codeine indirectly supports sleep is by reducing pain, which is a major barrier to restful sleep for individuals dealing with chronic pain conditions. By binding to opioid receptors in the brain, codeine helps reduce pain perception, thereby potentially enabling a more comfortable sleep environment. For some patients, this relief from pain leads to improved sleep duration and quality, especially in the early stages of use.

Codeine also has mild sedative properties that can initially feel beneficial for falling asleep. By slowing down central nervous system activity, it induces drowsiness and relaxation, which may contribute to a quicker onset of sleep. This sedation, however, is not equivalent to natural sleep, as opioids often suppress the body’s natural sleep-wake cycle. The sedation effects are also temporary.

While codeine can make falling asleep easier, it often disrupts sleep architecture or the natural progression of sleep stages that make rest restorative. Opioids, including codeine, are known to reduce the time spent in both REM sleep and slow-wave (deep) sleep, which are crucial for memory consolidation, emotional regulation, and physical repair. Codeine users often experience fragmented sleep due to these disruptions, with repeated awakenings and reduced sleep quality.

Negative impact of codeine on sleep quality

Codeine and other opioids depress the central nervous system, which includes reducing respiratory drive. This can lead to hypoventilation, where breathing becomes shallow or pauses, a condition known to exacerbate or induce sleep apnea. Individuals who already have respiratory issues, such as asthma or chronic obstructive pulmonary disease (COPD), are particularly vulnerable. Sleep apnea, a disorder characterised by repeated interruptions in breathing during sleep, can significantly disrupt sleep quality and increase the risk of cardiovascular issues over time.

As individuals use codeine over extended periods, tolerance develops, meaning higher doses are needed to achieve the same effect. This escalation can lead to physical dependency, where the body becomes reliant on the drug not only to relieve pain but also to initiate sleep. With continued use, codeine’s interference with sleep architecture results in sleep fragmentation, characterised by frequent awakenings and reduced time in restorative stages of sleep, such as REM and deep sleep. Additionally, individuals attempting to reduce or stop codeine use may experience withdrawal symptoms like insomnia, restlessness, and even rebound pain, which further interrupts sleep and can initiate a cycle of dependence.

Beyond its impact on sleep structure, codeine often causes side effects such as:

• Dizziness (contributes to difficulties in maintaining stable sleep)
• Nausea (can further disrupt rest)
• Headaches

Codeine dependency

Codeine is classified as an opioid, and like others in this drug class, it has a high potential for addiction. Addiction occurs due to the development of tolerance, where increasing doses are required to achieve the same pain relief or euphoric effects.

Symptoms and risk factors for codeine addiction

Several signs and symptoms indicate codeine dependency. These can include:

• Increased dosage requirements: Individuals may find themselves requiring higher doses of codeine to achieve the desired effects due to tolerance.
• Cravings and psychological dependence: Many dependent users experience strong cravings for codeine, particularly in situations associated with pain or discomfort.
• Withdrawal symptoms affecting sleep: Symptoms like insomnia, restlessness, and anxiety often appear when a person tries to reduce their intake, especially as their body begins to expect the drug for both pain relief and relaxation..

Withdrawal and sleep disturbances

Withdrawal from codeine often results in uncomfortable symptoms that severely disrupt sleep. Common withdrawal symptoms include:

• Insomnia
• Agitation
• Muscle aches
• Rebound pain, which is an intensified pain experience

These symptoms can lead to repeated awakenings, difficulty falling asleep, and non-restorative sleep. Withdrawal-related sleep disruptions make it challenging for individuals to regain natural sleep rhythms.

Myths about codeine and sleep

There are several myths about codeine, particularly in its role as a sleep aid or in its effects on sleep. Here are some common misconceptions:

1. Codeine is a reliable sleep aid

Codeine is a pain reliever and cough suppressant, not a sleep aid. While it may induce drowsiness, it doesn’t promote healthy, restorative sleep. Codeine belongs to the opioid class, which can alter sleep architecture, leading to disrupted REM (rapid eye movement) and deep sleep stages. This may cause people to wake up feeling less refreshed than expected.

2. Codeine helps you stay asleep longer

Although codeine can initially make people feel sleepy, it often leads to fragmented sleep. Opioids can reduce sleep quality by causing frequent awakenings and decreasing the time spent in deep sleep stages. Additionally, codeine can suppress breathing, increasing the risk of sleep apnea, which disrupts sleep continuity and quality.

3. Codeine is safe for long-term use as a sleep aid

Prolonged codeine use for sleep can lead to tolerance, dependence, and withdrawal symptoms. As tolerance develops, people may need higher doses to achieve the same drowsy effects, increasing the risk of side effects, addiction, and potentially life-threatening respiratory depression.

4. Codeine is non-addictive when used just for sleep

Codeine is indeed addictive, regardless of the reason for use. Dependency can develop even when it’s taken in smaller doses, especially when used frequently as a sleep aid. This can make it difficult for individuals to sleep without it, leading to dependence and potential misuse.

5. Codeine doesn’t affect sleep quality in low doses

Even in low doses, codeine can alter sleep stages and impair the overall quality of sleep. Some people are more sensitive to opioids, and even small amounts of codeine can have significant effects on their sleep cycle.

6. Codeine is a natural solution for sleep

Codeine is derived from opium, but this doesn’t make it a natural or benign solution for sleep. Opioids are powerful drugs, and codeine’s origin in natural substances doesn’t eliminate its risks or side effects.

For better sleep, safer approaches include sleep hygiene practices, regular sleep schedules, and non-addictive sleep aids recommended by a healthcare provider. Codeine is generally reserved for its primary uses in pain relief and cough suppression, and it should be used with caution under medical supervision.

For individuals using codeine, it is essential to approach the medication carefully. Before considering long-term use, it is advisable to consult a healthcare provider to evaluate both the potential benefits and risks. Discussing dosage, duration, and alternative options can be particularly helpful in avoiding dependency.