Codeine vs Hydrocodone: Strength, Safety, and Key Differences

Codeine and hydrocodone are two prescription opioids prescribed by doctors to treat acute pain resulting from injuries, surgery, or chronic pain associated with diseases or conditions like cancer, fibromyalgia, or back pain. 

Prescription opioids can cause side effects, and while most are mild and temporary, there are risks of dependency and addiction.

Are Hydrocodone and Codeine the Same Medications?

No. Hydrocodone and codeine are not the same medication. Codeine is a naturally-derived opioid found in the opium poppy plant. It was the first opioid to be isolated from plants. Codeine was originally used to treat colds, coughs, diarrhea, and pain. 

Today, however, it is primarily used to treat pain. The FDA approved codeine for the treatment of mild to moderately severe pain.[1] Although codeine is a relatively weak opioid, it still carries a risk of dependency and addiction.

Hydrocodone is a semi-synthetic opioid developed in the 1920s. It is created by modifying morphine in a laboratory. Morphine is a naturally derived opioid from the opium poppy plant. This modification creates significant differences in the strength and metabolism of both medications. Hydrocodone is significantly stronger than codeine. The FDA approved hydrocodone for the treatment of moderate to severely painful conditions.[2] Like codeine, hydrocodone carries a risk of dependency and addiction.

Although codeine and hydrocodone have different strengths and are used to treat different types of pain, both can be habit-forming. Misuse of prescription opioids is common among young adults. 

According to data released by the Substance Abuse and Mental Health Services Administration (SAMHSA) in 2018, an estimated 1.9 million young adults aged 18–25 misused prescription pain relievers, representing 5.5% of young adults in the United States.[3]

As noted above, both medications belong to the opioid class, so it is understandable that many people confuse them. However, just because both medications are members of the same class does not mean they are the same medication.

Do Products Containing Hydrocodone Have Codeine in Them?

Products containing hydrocodone do not have codeine in them. Examples of commonly used products containing hydrocodone are:

• Vicodin (hydrocodone-acetaminophen) 
• Norco (hydrocodone-acetaminophen)

These products combine hydrocodone with acetaminophen (Tylenol). Many products containing codeine are also combined with acetaminophen or are used in cough medicines. However, hydrocodone and codeine are never mixed together in a single product.

Codeine vs. Hydrocodone at a Glance

Is Hydrocodone Stronger Than Codeine?

Yes. Hydrocodone is generally stronger than codeine for treating pain. When comparing codeine and hydrocodone in terms of strength, it’s essential to recognize that strength refers to how well an opioid binds to opioid receptors in the central nervous system (the brain and spinal cord), not necessarily the amount of the opioid present in a particular pill or tablet.

Because hydrocodone has a greater affinity for opioid receptors than codeine, it requires less of itself to produce comparable levels of pain relief. The amount needed to achieve desired results can be significantly less than codeine. In addition, hydrocodone tends to be faster-acting than codeine.

There are times when the fact that hydrocodone is stronger is not the determining factor in deciding which medication is correct for an individual. Factors such as type of pain being treated, individual risk factors for dependency and/or addiction, other medical problems, and previous use of opioids also play major roles in making a decision regarding which medication is more suitable.

How Do Codeine and Hydrocodone Compare Regarding Side Effects and Dependency Risk?

Both medications can produce many similar side effects due to their mechanism of action as opioids:[4]

• Drowsiness
• Lightheadedness
• Constipation
• Nausea
• Slowed breathing

Both hydrocodone and codeine carry risks of tolerance, physical dependence, and misuse because they are opioid medications. Hydrocodone has demonstrated abuse potential due to its opioid effects, including euphoria in controlled studies.[5] Prolonged opioid use can also lead to tolerance, in which higher doses may be needed to achieve the same effect.

Misuse Potential Between Codeine and Hydrocodone

Both medications have the potential for misuse. Misuse includes taking a medication more frequently than directed by a doctor or taking a larger dose than directed. Misuse of either medication increases the likelihood that an individual will become dependent upon it.

Risk Signs Indicating Problematic Opioid Use

Some warning signs indicating that an individual may be experiencing problems with opioids include:

• Taking an opioid in a manner other than prescribed
•  Seeking additional prescriptions for an opioid from multiple physicians
• Using an opioid for reasons other than relieving physical pain (for example: to relax or for recreational purposes) 
• Continuing to use an opioid despite experiencing serious consequences or difficulties as a result of continued use

Withdrawal Symptoms Caused by Stopping either Opioid Suddenly After Long-Term Use

If an individual stops using codeine or hydrocodone after long-term use, withdrawal symptoms may occur. Withdrawal symptoms include:

• Anxiety 
• Restlessness
• Muscle aches
• Sweating
• Nausea
• Trouble sleeping

While withdrawing from an opioid is uncomfortable for most people, withdrawal can also create serious medical issues for some individuals. When attempting to discontinue either medication, medical oversight is highly encouraged.[6]

Options Available for Managing Safe Withdrawals from Codeine or Hydrocodone

Withdrawal from opioids can be managed safely through various methods that may include medically monitored detoxification at a treatment center.

Structured treatment offers a degree of support that many individuals find challenging to provide themselves. Treatment centers provide medical professionals, counselors, therapists, and peer support groups to assist with each phase of recovery.

Drug Schedules and Classification for Codeine and Hydrocodone

Both codeine and hydrocodone are regulated by the DEA under federal laws prohibiting the possession or distribution of controlled substances without proper licensure or authority. Additionally, both codeine and hydrocodone require valid prescriptions from licensed physicians to purchase. Depending on the actual formulation of the medication(s), these controlled substances can be classified under different schedules as follows:[8]

Schedule II: These drugs have a high potential for abuse with severe psychological or physical dependence liability, but accepted medical use exists for treatment in the United States or with extreme limitations. Most hydrocodone combination products fall under this classification.

Schedule III: Moderate to low potential for physical dependence with high potential for psychological dependence. Accepted medical use exists for treatment.

Schedule V: Low potential for abuse relative to Schedule IV drugs. Abuse of a drug in this schedule would lead to limited physical or psychological dependence relative to Schedule IV drugs. Certain low-dose cough formulations containing codeine fall into this category.

Regulatory Bodies Involved With Opioids

The FDA reviews new medications for approval based on scientific evidence demonstrating efficacy and safety. Regulatory bodies involved with tracking national trends concerning prescription opioid abuse include the CDC. [8] Due to variations in classifications depending on exact formulation, pharmacists or prescribing physicians can identify how a particular prescription fits within one of these schedules.

Comparative Analysis Between Other Prescription Opioids

Codeine and hydrocodone represent two examples of prescription opioids designed for treating pain, but additional prescription opioids include:

• Oxycodone 
• Hydromorphone
• Fentanyl

Each of these prescription opioids possesses unique characteristics regarding their strength and potency levels and clinical applications ranging from treating moderately severe pain to severe pain experienced during acute episodes (hospital settings).

Non-opioid pain medications (over-the-counter and prescription) should always be attempted prior to using prescription opioids for mild pain. Interactions between medications and opioids must be monitored closely, as combining CNS depressants, antidepressants, or other analgesics may exacerbate undesirable side effects or reactions.[9]