Morphine is an opioid full agonist and can be addictive if misused. It should only ever be taken as recommended by medical professionals.
What Makes Morphine Addictive?
Morphine is primarily addictive because of how it acts on the brain.
Morphine is isolated from the opium poppy. Both natural and semisynthetic opioids are all produced (at least in part) from this plant.
Morphine acts upon opioid receptors in the brain to block pain and produce euphoria. This effect gets stronger with higher doses. Like all opioids, morphine’s effects on the brain can cause addiction if not used with care.
Prolonged morphine exposure causes cells to “rewire” and express more opioid receptors. This causes an increased craving for more opioids, leading to physical dependence and addiction. With more receptors needing to be stimulated, a person develops tolerance. Conversely, without the drug, those receptors are unoccupied and produce dysphoria and other symptoms of withdrawal, prompting people to crave more opioids and promoting a vicious cycle.
This physical dependence isn’t the only factor in addiction, but it is an important one. Other important factors include psychological dependence, where a person feels they need to use drugs to compensate for problems in their life or otherwise feel “normal.” This is why comprehensive addiction treatment tackles not only physical dependence, but also the underlying causes of why a person uses drugs in the first place.
How Addictive Is Morphine?
All opioids are considered highly addictive when misused. Morphine, like other opioids, carries a high risk of addiction. It carries relatively similar rates of addiction as other full opioid agonists such as oxycodone, hydrocodone, hydromorphone, heroin, or fentanyl. 
What Is Happening in the Body When You Take Morphine?
Opioids bind to and activate opioid receptors that are present on cells in the body, including your brain and spinal cord. This causes pain signals to be blocked from reaching the brain. In this way, it serves as a powerful analgesic.
At the same time, morphine triggers the release of large amounts of dopamine, producing a sense of euphoria. This euphoria, when created over prolonged use, can lead to physical dependence and addiction.
At the base of the brain is the locus coeruleus (LC), which is responsible for wakefulness, breathing, blood pressure, alertness, and more. When opioids bind to neurons in the LC, these systems are affected, which causes several of the more undesirable and dangerous effects associated with opioid use, notably respiratory depression (which can be deadly in the case of an overdose). 
Treatment Options if You’re Addicted to Morphine
An opioid addiction of any kind is serious. Over 2.5 million Americans were diagnosed with opioid use disorder in 2014. Treatment is available in several forms, and it generally works best when overseen by an addiction treatment specialist.
Several medications can treat opioid use disorder through Medication for Addiction Treatment (MAT), including buprenorphine (Suboxone) and methadone.
MAT is not just medication. MAT programs also include the use of therapy and other supportive measures to achieve and sustain sobriety. Individual, family, and group addiction counseling can help a person identify what causes them to use drugs beyond physical dependence and work to control those impulses in a healthier way.
Often, the best way to get started with recovery is to talk to an addiction treatment specialist about your needs. This professional can help you customize a treatment plan that maximizes your chance of recovery.
Recovery isn’t a quick fix, and using a medication like Suboxone doesn’t mean you’ll be cured of opioid use disorder. There is no cure for addiction, as it’s a chronic condition, but it can be effectively managed for life. Many people remain on MAT like Suboxone for years or even indefinitely, as it continues to support their recovery. Talk to your doctor about MAT if you think it might be a good choice for you.