Pain is an important alarm system in your body that tells you when something’s wrong. However, it can also complicate treatment and recovery when pain is too strong. Opioids are often used to treat moderate to severe pain symptoms. Two of the most common opioids that are used in pain relief are codeine and hydrocodone. They are both relatively mild opioids when compared to other options, and they’re both mixed with other non-opioid pain relievers to increase their effectiveness. But which of these drugs is the most effective when treating pain?
What Are Opioids?
Opioids are a class of drugs that have been used by humans for thousands of years. They occur in nature and are most commonly derived from the opium poppy plant. The seeds of that plant have been found in human civilizations as early as 5,700 BC. In modern history, opioids have been used as medications to treat pain since the 17th century, when a tincture of opium and alcohol was introduced under the name laudanum. The terms opium, opiate, and opioid are often used interchangeably, but they refer to different things.
Opium refers to the opium poppy plant or the milky sap that comes from that plant that contains psychoactive chemicals. Opium has the earliest uses as a pain reliever, ritual drug, and recreational substance. Opium was also a major commodity in the 17th and 18th centuries. Countries like India, Portugal, the Netherlands, Britain, and China traded the substances for major profits.
However, it wasn’t until the 18th century that the first opiate was isolated from opium poppy plants. Opiates are naturally occurring chemicals that have a distinct structure that is able to bind to opioid receptors in the human brain. Morphine was the first drug to be isolated from the plant in 1804. Codeine was also later isolated in 1832. Both morphine and codeine are opiates.
Opioids are chemicals that are made by altering an opiate or by creating an opioid chemical in a lab. The word opioid can also be used to refer to all drugs that have the opioid chemical structure, including natural and synthetic drugs. Drugs that are made with the use of a natural opiate are called semisynthetic opioids. Opioids that are made in a lab without a natural starting place are called synthetic opioids. Heroin, also called diamorphine, was the first semisynthetic opioid to be invented. It was made by boiling morphine with a chemical compound called acetic anhydride.
Opioids have been used for a variety of medical purposes in the past. In addition to treating pain, they have also been used to treat coughs and diarrhea. Today, there are several opioids that are used to treat moderate to severe pain symptoms. They may be used to treat acute pain and chronic pain issues.
How Do Opioids Treat Pain?
Opioids are the current gold standard for treating severe pain symptoms that are caused by injuries, surgery, and other sources of pain. Opioids work by binding to opioid receptors in the brain. These receptors are naturally designed to bind with neurotransmitters called endorphins. Endorphins were discovered after the isolation of morphine, and it was the first time researchers realized that opioids occur in the brain naturally. The name endorphins are even short for “endogenous morphine” because of how similar morphine is to your natural pain-managing brain chemicals.
Endorphins work by binding to opioid receptors in the brain and blocking pain signals from being sent and received throughout the body. They can bind at the site of pain, in the spine, and in the brain so that they are present everywhere along your nervous system’s pain trail. Your endorphins are designed to manage pain but not to stop it entirely. Pain is your body’s alarm system that tells you when something is wrong. Blocking pain entirely all the time can be dangerous. However, moderate and severe pain can be overwhelming, and opioid medications can stop it with more potency than your natural endorphins.
Opioid medications not only help to stop pain but also allow you to relax and recover after an injury or another cause of acute pain. Opioids are also used to treat chronic pain in some cases. Chronic pain refers to pain that can last for long periods of time because of chronic diseases, spinal cord injuries, and neurological damage. Opioids can be useful in managing some sources of chronic pain, but they also come with serious downsides. Opioids are addictive, and they can cause chemical dependence and substance use disorder. They may cause these problems when misused, but they can also cause them when the drugs are used for too long.
What Is Codeine?
Codeine is an opiate found in opium poppy plants. It’s also used in medical settings and sold in prescription drugs. Codeine is a prodrug of morphine, which means that the body breaks down codeine and turns it into morphine. Codeine and morphine both bind to a specific type of opioid receptors called mu-opioid receptors (MOR). However, codeine has a weak affinity for MOR, which means that it doesn’t bind as easily as other opioids. If it were to remain as codeine, it would have limited effects. However, when you take codeine, it’s quickly broken down in the body, which produces morphine. Morphine binds to MOR much more easily and has significant pain-relieving effects. Codeine is also broken down into a metabolite called codeine-6-glucuronide, which can also bind to MOR.
Since codeine is a weak MOR agonist on its own, it’s much less potent than other opioid medications for treating pain. To achieve the same pain-relieving effects as 30 mg of morphine, you’d have to take 200 mg of codeine.
However, codeine’s relative potency hasn’t stopped it from becoming a widely used medication all over the world. Codeine is used to treat pain, and it’s especially used to manage pain symptoms after dental surgeries. It’s still used to treat coughs in adults, but the evidence for its usefulness as a cough suppressant is controversial. It’s also used to treat diarrhea since opioids can bind to receptors in the bowels to slow down activity that might contribute to diarrhea.
Codeine is also a useful substance in drug combinations and formulations. Codeine is often combined with other non-opioid pain relievers like paracetamol. It’s also combined with aspirin and ibuprofen. Combining it with these other drugs can help increase its pain-relieving potential and address common causes of pain like inflammation.
What Is Hydrocodone?
Hydrocodone is a semisynthetic opioid that’s also used to treat severe pain and coughs. It’s specifically used to treat pain symptoms that require long-term management. The drug was first patented in 1923. It was later approved by the U.S. FDA in 1943, and it’s currently most commonly used in the United States. Hydrocodone is a highly selective MOR agonist. That means that it readily binds with MORs and is much less likely to bind with other opioid receptors like delta and kappa opioid receptors.
Still, just like morphine, hydrocodone is much less potent than morphine when it comes to pain relief capability. When the drugs are taken intravenously, hydrocodone is about a tenth the strength of morphine. However, hydrocodone is about as effective as morphine when the drugs are taken by mouth because morphine is more inefficient when taken by mouth.
Hydrocodone is only available as an oral medication, but it can also be combined with other drugs, including paracetamol and ibuprofen. It may be combined with these drugs for the same reason that codeine is, allowing the formulation to have greater effects in treating pain and inflammation. Hydrocodone may have some specific uses in treating pain from particular sources. Hydrocodone was found to be effective in treating bone fractures when compared to oxycodone in a 2008 study. Before this, it was thought that oxycodone was 50 times more effective than hydrocodone, but the study found that they were equally effective in treating fractures.
One of the most common opioid brands is Vicodin, which contains hydromorphone mixed with acetaminophen. Vicodin is a commonly used pain reliever, but it’s also commonly used as a recreational substance. Vicodin comes with the warning to use it with caution after non-opioid pain relief options have been explored.
Does Hydrocodone Have Codeine in It?
Hydrocodone and codeine have similar-sounding names, which may cause some people to assume that hydrocodone contains codeine. However, there are two similar but different chemical compounds. However, hydrocodone does have a special relationship to codeine over other opioids. Hydrocodone is a semisynthetic drug that’s made from altering codeine by adding oxygen to it. It was originally developed by a German company to try to create a version of codeine that didn’t have codeine’s side effects, but the end result was a more powerful opioid with a similar side effects profile.
Does Codeine or Hydrocodone Provide More Pain-Relief?
When you and your doctor are considering prescription drug options, there are several variables to consider. When it comes to opioid pain-relievers, there is no one ideal option. People may react differently to different drugs, and pain management may require careful adjustments from your medical team. You may need to change medications or adjust your dose to avoid side effects and get the best relief. Most of the time, the most potent opioid isn’t necessarily the best option. Since opioids can cause some uncomfortable side effects and serious issues like dependence, the mildest possible option may be the best for your needs. However, there are some things to consider when it comes to the relative pain-relieving effectiveness of each drug.
The size of an effective dose can be a good indication of a drug’s strength when compared to other similar drugs. When comparing the relative potency of different pain-relieving drugs, medical professionals and clinicians may use something called an equianalgesic dose chart. These charts show the size of the dose of different drugs with the same pain-relieving effectiveness. Most charts show that a 30 mg dose of hydrocodone is equal to a 200 mg dose of codeine. However, codeine can cause a wide range of reactions when used in real-life pain management. Plus, equianalgesic dose charts are often criticized for accuracy. Still, it shows that hydrocodone is generally more potent than codeine when it comes to pain relief.
Onset and Duration of Action
The onset of action and the duration of action are major considerations when taking prescription drugs. Acute pain that needs immediate relief requires a fast-acting drug, even if it doesn’t last very long. In some cases, pain needs to be taken care of immediately before medical professionals can address the problem that’s causing it. Sometimes the duration of action is more important, especially when it comes to long-term pain management. When chronic pain needs to be treated over a long period, your doctor may avoid having you take medication every few hours, opting for longer durations of action.
However, morphine and codeine have fairly similar time frames in both categories. However, codeine tends to start working more slowly and may take up to 45 minutes before you feel significant effects. Hydrocodone may begin working between 10 and 30 minutes.
Hydrocodone and codeine have similar durations of action, both wearing off after around four to six hours.
What Are Their Side Effects?
Some of the most common side effects of opioid use include sedation, constipation, and itchiness. Opioids can block pain receptors, but they also work to slow down the nervous system, which can cause some effects that are similar to central nervous system depressants. Powerful opioids can cause sedation and drowsiness that make certain activities more difficult or unsafe. However, even weaker opioids like codeine and hydrocodone can cause a feeling of sedation.
For the same reason that opioids can be used to treat diarrhea, they can also cause constipation. Opioids can slow down functions in your intestines and digestive system to cause constipation. People that take hydrocodone or codeine for pain relief without any digestive issues often experience constipation, which can be frustrating or distressing for people dealing with pain symptoms.
In some cases, especially when they’re taken by mouth, opioids can cause nausea and vomiting. Both codeine and hydrocodone are associated with nausea in some cases. It may help to speak to your doctor about adjusting the dose to avoid some uncomfortable side effects.
Side Effects of High Doses
High doses of hydrocodone and codeine increase your risk of more serious side effects. Opioid overdose can be deadly, and it’s one of the driving causes of overdose death rates each year. Since opioids can slow down the central nervous system as a depressant can, the consequences of an opioid overdose are similar to depressant overdoses. Hydrocodone and codeine can help to relax a person in pain by slowing down some nervous system activity. But high doses can start to slow down vital unconscious functions of your nervous system, including your breathing and heart rate.
One of the most dangerous consequences of an opioid overdose is respiratory depression. Respiratory depression is when your breathing slows to a dangerous degree or stops completely. It can cause hypoxia, oxygen deprivation, and brain damage that’s caused by a lack of oxygen. Opioid overdoses can be reversed with a drug called naloxone that binds to opioid receptors and blocks them, kicking off any opioids. This sends you into a state of immediate withdrawal, but it can save your life. However, if naloxone isn’t administered in time, opioid overdoses can be fatal, or they may cause permanent impairments.
Other side effects that are associated with high doses include pinpoint pupils, coming in and out of consciousness, changes in heart rate, hypothermia, and coma.
Side Effects of Long Term Use
Using codeine or hydrocodone for a long time can lead to some significant consequences. Long-term use may be seen with the management of chronic pain symptoms, but it may also occur with misuse or abuse. One of the first consequences of long-term opioid use is tolerance. Tolerance is the diminishing effectiveness of the drug’s intended effects because your brain and body are adapting to it. Opioid-resistant patients often have a hard time getting relief from pain symptoms.
In the same vein, long-term opioid use can cause hyperalgesia, which is an increased sensitivity to pain. This is referred to as a paradoxical side effect, which is an effect of a drug that is the opposite of its intended use. This may happen as your body adapts to the drug in your system. Because your pain signals are being suppressed, your body may produce more pain receptors to ensure they are functioning normally, but they actually cause increased sensitivity to painful stimuli.
Another potential side effect of long-term opioid use is drug dependence. Dependence is another consequence of your body’s ability to adapt to a drug in your system. As your brain chemistry adapts, it will begin to rely on the drug to maintain normal chemical balance. If you stop using an opioid after you develop a chemical dependence on the drug, you may experience uncomfortable withdrawal symptoms. Opioid withdrawal symptoms include nausea, vomiting, diarrhea, sweating, body aches, and fatigue. Because of these symptoms, opioid withdrawal is often compared to a particularly bad case of the flu. It is usually not life-threatening, but it can cause dehydration, which can be dangerous. It’s also difficult to get through without relapse, especially when these symptoms are combined with drug cravings.
Finally, long-term opioid use has the potential to cause addiction and opioid use disorders. Addiction is defined as compulsive drug use that gets out of control. It may be identified when you continue to use drugs despite serious consequences to your health, relationships, finances, or other areas of your life. Serious opioid use disorders often require treatment for a person to achieve lasting sobriety.
Is Codeine or Hydrocodone More Addictive?
A drug’s addictive potential is hard to measure, especially when both drugs are so similar. Both hydrocodone and codeine are categorized as Schedule II drugs in the United States, which means they are federally controlled substances with abuse potential, even though they do have some medical uses. However, codeine formulations that include other drugs are in less restrictive categories between Schedule III and V. There are several factors in a drug’s abuse and addiction potential. One of the most common factors is the drug’s ability to interact with dopamine, a neurotransmitter that’s tied to reward and pleasure in the brain. Opioids have been found to increase the release of dopamine in the brain, which can cause a euphoric sense of relaxation, especially when combined with potent pain relief.
However, there are other factors that may contribute to a drug’s addiction and abuse potential. Addiction is more likely when a drug is misused or used recreationally. Recreational drug users tend to gravitate toward drugs that start working fast and have a relatively short duration of action. Generally, when you’re using a drug for euphoric effects, you want it to wear off before it overstays its welcome. Drugs that cause an initial sense of euphoria followed by hours of drowsiness and other side effects usually have lower abuse potential. This may be illustrated by a study that found that extended-release hydrocodone had a lower abuse potential than immediate-release hydrocodone.
Hydrocodone may begin working in 10 to 20 minutes, depending on the formulation and other factors. Since codeine needs to be broken down into morphine in the body before it becomes active, it can take longer to take effect. It may begin working within 30 to 45 minutes, which may be a long time to wait when you’re seeking a recreational high.
Another factor is availability. This may trump other factors because curious would-be recreational substance users may gravitate toward the drug that is the easiest to get. Both hydrocodone and codeine are extremely common. However, Vicodin is one of the most common opioid-containing brand drugs, which is commonly misused.