Codeine and hydrocodone are both opioids that are commonly prescribed for pain. They have many similarities, including side effects and risks, but hydrocodone is stronger.
While they can be effective for treating pain, both codeine and hydrocodone have a high potential for misuse and addiction. Learn more about the similarities and differences between codeine and hydrocodone, their side effects and risks, and how to determine if they’re right for you.
What Is Codeine?
Codeine is an opioid that’s prescribed for the treatment of mild pain and cough. It’s in the class of antitussives (cough suppressants) and opioids (narcotic analgesics).
It has a lower potency than comparable prescription opioid pain relievers, so it’s often combined with other drugs like acetaminophen. As a cough syrup, codeine is fairly mild. Some formulations with low amounts of codeine may be available over the counter.
Though codeine is less potent than other opioids, it still has the potential for misuse, abuse, and addiction. Codeine preparations vary, so they range from a Schedule II to a Schedule V controlled substance.[1]
What is Hydrocodone?
Hydrocodone is a common opioid pain medication that’s often combined with acetaminophen to relieve moderate to severe pain and nonproductive cough in adults. It’s in the class of antitussives and narcotic analgesics.
Typically, hydrocodone cough syrup is used in patients with coughs and severe pain, such as those from lung cancer.
As a potent opioid, hydrocodone is highly addictive. It’s common for people to develop physical dependence with hydrocodone, and it may be misused to get high. Hydrocodone is classified as a Schedule II controlled substance.[2]
Forms and Dosages of Codeine and Hydrocodone
Codeine is available in immediate-release oral tablets with 15-mg, 30-mg, and 60-mg strengths, typically taken every four hours as needed.[3]
Hydrocodone comes in immediate-release oral tablets combined with acetaminophen. Tablets are available in 2.5-mg, 5-mg, 7.5-mg, and 10-mg strengths, taken every four to six hours as needed.[4]
Hydrocodone is only available in extended-release oral tablets ranging from 10 to 120 mg.[5] Depending on the dose, they may be taken every 12 or 24 hours. These higher strengths are usually reserved for patients who have been on hydrocodone for a while and need higher dosages for relief.
Side Effects and Risks of Codeine and Hydrocodone
Both codeine and hydrocodone have some side effects, such as drowsiness, dizziness, constipation, and nausea or vomiting, which are common for most opioids. Codeine may also cause lightheadedness, shortness of breath, and sweating, while hydrocodone may cause itching and loss of appetite.[6]
The side effects may be more pronounced in older people, people with liver or kidney disease, chronic obstructive pulmonary disease, or other chronic diseases.
Codeine and hydrocodone also have significant risks, especially if they’re not taken as prescribed. High doses of either drug can cause additional side effects like infections, liver damage, and urinary retention.
Long-term use of codeine and hydrocodone can cause dependence, which is when the body becomes used to the presence of a drug. If you stop taking either one or dramatically reduce your dose, you may experience withdrawal symptoms that include:[7]
- Nausea and vomiting
- Trouble sleeping
- Anxiety
- Hot and cold flashes
- Sweating
- Muscle cramps
- Watery discharge from the eyes or nose
- Diarrhea
Potential Interactions with Codeine and Hydrocodone
Codeine and hydrocodone are opioids that affect the central nervous system, so they can be dangerous to mix with other medications that have similar effects, such as:[8]
- Muscle relaxants
- Anticholinergic drugs like antihistamines
- Barbiturates
- Antiseizure medications
- Antidepressants
- Antipsychotic drugs
- Alcohol
- Sedatives, tranquilizers, and sleeping pills
- Other opioid medications
Combining opioids like codeine or hydrocodone with these drugs can cause serious and potentially fatal side effects like:
- Low blood pressure
- Respiratory distress
- Fainting
- Coma
- Death
Codeine vs. Hydrocodone: Key Differences
Codeine and hydrocodone are prescribed to treat pain and help with cough by suppressing the cough reflex in the brain. However, they have several differences:
- Codeine and hydrocodone have different chemical structures. Codeine is a natural opioid derived from opium, while hydrocodone is a semi-synthetic opioid.
- Hydrocodone can be effective in anyone, but not everyone gets an effect from codeine. It requires the liver enzyme CYP2D6 to turn it into morphine. If someone lacks this enzyme, they won’t feel any effects.
- People may think they’re experiencing an allergic reaction to codeine because of symptoms like itching and nausea. These side effects are normal and caused by the way codeine activates the histamine response in the body. Hydrocodone doesn’t have this side effect.
- Hydrocodone is a much stronger opioid than codeine and leads to stronger sedative and pain-relieving effects.
However, both codeine and hydrocodone bind to the opioid receptors in the brain and depress the central nervous system, which can lead to overdose.
Addiction Risks of Codeine and Hydrocodone
Both codeine and hydrocodone carry a risk of addiction, but hydrocodone is the more potent and addictive of the two. As opioids, addiction to either codeine or hydrocodone is classified as an opioid use disorder (OUD).
The criteria for OUD in the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) include:[9]
- Taking larger amounts of opioids or for longer periods than intended
- Persistent desire or unsuccessful efforts to control opioid use
- Spending a lot of time obtaining, using, or recovering from opioids
- Experiencing cravings for opioids
- Problems fulfilling obligations at work, school, or home
- Continued opioid use despite recurring social or interpersonal problems
- Giving up or reducing activities because of opioid use
- Using opioids in dangerous situations, like driving under the influence
- Continued opioid use despite ongoing physical or psychological problems
- Tolerance, or the need for increased amounts or diminished effect with continued use of the same amount
- Experiencing withdrawal or taking opioids to relieve withdrawal symptoms
Opioid addiction is difficult to overcome, but effective treatments are available. Typically, treatment begins with a medical detox to manage the symptoms of withdrawal. This setting includes 24/7 medical supervision and medications to keep you safe and comfortable.
After detox, formal addiction treatment is recommended, which may include medications to reduce cravings and behavioral therapies like cognitive behavioral therapy to encourage change and prevent relapse.
Seek Help for Opioid Addiction
Both codeine and hydrocodone are commonly prescribed for pain and cough. While both can be effective, they each carry a risk of misuse, abuse, and addiction. If you or a loved one is struggling with opioid addiction, it’s important to seek help to avoid the risk of serious side effects or overdose.
