Oxycodone vs. Morphine: Is One More Addictive?

Oxycodone is believed to be somewhat more addictive than morphine due to its higher potency. But both drugs are very addictive.

Understanding Oxycodone & Morphine 

Oxycodone is a semisynthetic narcotic pain reliever that is synthesized from the poppy plant. It is legally prescribed for the treatment of moderate to severe pain, such as following an injury or surgery, or to cancer patients. 

Oxycodone is available in immediate-release and extended-release forms, depending on the needs of the patient. It produces effects similar to morphine.[1]

Morphine is a non-synthetic narcotic pain reliever derived from opium. It reduces physical pain, inhibits appetite, and can be used to treat severe cough. 

Morphine is consumed via intravenous injection, oral solution, and immediate and extended-release tablets and capsules. Like oxycodone, morphine produces a pleasurable high that people can quickly become addicted to.[2]

How Do Morphine & Oxycodone Work?

Morphine and oxycodone work by interfering with opioid receptors throughout the body. They bind to receptors in the brain, spinal cord, and other organs to block the perception of pain. The medications can be swallowed, injected, or snorted in cases of misuse.[3] 

In addition to reducing pain, opioids can cause people to feel relaxed, happy, and sometimes euphoric. Such positive feelings reinforce opioid use and dangerous drug use habits. 

Once addicted, medications and behavioral therapies are likely needed to treat opioid use disorder (OUD).[3] If someone attempts to stop the use of morphine or oxycodone suddenly after addiction has taken hold, they will experience uncomfortable withdrawal symptoms. Relapse is very likely during this time.

Comparing Oxycodone & Morphine

Oxycodone and morphine are two of the most prescribed prescription opioids. Knowing how they compare can better inform their safe use. Use the table below to better understand how oxycodone and morphine are similar and different.[4-9] 

	Oxycodone	Morphine
Brand Names	Oxycontin, Oxaydo, Xtampza ER, Roxicodone	Arymo ER, Kadian, Morphabond, MS Contin
Drug Class	Opioid analgesic	Opioid analgesic
Formulations	Extended- or immediate-release tablets, capsules, and solutions	Capsules, tablets, liquid solutions, and injectable solutions
Prescribed For	Moderate to severe pain	Moderate to severe pain
Onset	Within minutes for immediate-release versions and slightly longer for extended-release formulations	Within minutes for immediate-release versions, and nearly immediately for intravenous solutions
Duration	4–6 hours for immediate-release formulations and 12 hours for extended-release capsules	4 hours for oral immediate-release formulations, and 8–24 hours for various extended-release versions
Potential for Abuse	High with prolonged use	High with prolonged use
Safety for Children	Not advised for children under 11 years old	Tablets are considered safe for children weighing at least 110 pounds; the solution can be prescribed for children at least 2 years old
Insurance Coverage	Covered by most plans when prescribed by a doctor, though copays may still apply	Covered by most plans when prescribed by a doctor, though copays may still apply

Is One Medication More Addictive or More Effective?

The effectiveness of oxycodone or morphine depends on the individual’s level of pain, needs, and personal response to the medication. However, a 2018 study found that both oxycodone and morphine are equally effective in managing pain. A meta-analysis of studies of cancer patients with moderate to severe pain found that both oxycodone and morphine effectively reduced pain without significant negative side effects.[6]

While the drugs are equally effective in treating pain, oxycodone is much more potent than morphine and thus likely to be more addictive. Oxycodone is 1.5 to two times as potent as morphine.[7] 

Due to its potency and potential for euphoric side effects, oxycodone is a popular drug of misuse. People who are addicted to oxycodone may swallow the tablets or crush them up and either snort them or dissolve them in water and inject the solution.[1]

Common Side Effects of Oxycodone & Morphine

As prescription opioids, oxycodone and morphine share similar side effects. The intensity of the side effects depends on the amount of the drug consumed and the individual’s response to the drug. 

Common side effects of oxycodone and morphine include the following:[3]

• Drowsiness
• Confused mental state
• Nausea and vomiting 
• Constipation
• Euphoria 
• Slowed breathing 

It is important to monitor the side effects of opioids closely, as they can lead to overdose. As central nervous system depressants, oxycodone and morphine can depress breathing and heart rate severely. Overdose on either drug could be fatal. 

Who Shouldn’t Take These Drugs?

Older people taking opioids are advised to do so with extreme caution. Older adults are more likely to suffer from various health conditions and take multiple medications, which can lead to dangerous medication interactions within the body and accidental misuse.

Likewise, pregnant women are advised against taking opioids, as they can lead to miscarriage, low birth weight, and neonatal abstinence syndrome. Babies born with opioids in their system may suffer withdrawal symptoms, which can be life-threatening, and require medication when born.[3]

People taking opioids are warned against the dangers of consuming alcohol at the same time. Alcohol is also a central nervous system depressant and increases the likelihood of overdose when consumed with opioids. Together, the substances can suppress breathing and heart rate to dangerously low levels. 

The Risk of Abuse With Oxycodone & Morphine

Although oxycodone is more commonly abused, addiction can develop to both types of opioids. Both drugs should only be taken exactly as prescribed and under a doctor’s supervision. 

If you’ve been misusing either drug, it’s not easy to stop on your own. Fortunately, many evidenced-based treatment methods are available, including the use of medication-assisted treatment (MAT), which combines the use of medications like buprenorphine and behavioral therapies.[10] Recovery from any opioid use disorder is possible with the right help.