Morphine Addiction: Symptoms, Signs & Side Effects

Morphine is a strong pain medication that works by acting on opioid receptors in the brain. When morphine activates these opioid receptors, it suppresses nerve signals that transmit pain, reducing the sensation of pain. In addition to suppressing pain signals, increased activation of the opioid receptors also creates an increase of certain chemicals in the brain called endorphins which cause a pleasurable, euphoric sensation called a high. Sometimes those who use morphine may become addicted to the high that morphine causes and experience signs of morphine addiction.

When morphine is used over a prolonged period, people may develop tolerance and dependence. Tolerance to morphine occurs when the brain adjusts to the dose of morphine consistently used and stops making a high. This change means that it takes higher doses to create a high. Dependence is when the body adjusts to the presence of morphine and starts requiring morphine to function normally. When morphine is no longer used, the body starts experiencing withdrawal symptoms.

Symptoms of Morphine Abuse

There are two ways in which symptoms of morphine abuse may be noticed. The first is the physical effect that misusing morphine has on the body of the person misusing it and the second is social and behavioral changes that can occur with addiction.

Physical morphine symptoms that may occur when morphine is being misused include:

  • Euphoria
  • Drowsiness
  • Flushed skin
  • Itching
  • Nausea
  • Vomiting
  • Constipation

Those who misuse morphine may also experience symptoms of withdrawal when morphine use is stopped. General withdrawal symptoms include:

  • Feeling sick
  • Stomach cramps
  • Muscle spasm or twitching
  • Feeling chilled
  • Palpitations
  • Achiness or soreness
  • Watery eyes
  • Problems sleeping
  • Seizures

Common behavioral or social symptoms of addiction include:

  • Increased agitation, anxiety or irritability
  • Decreased social interactions
  • Disruptions to previously stable relationships
  • Financial problems
  • Decreased performance at work or school

While not all of these symptoms are specific to morphine misuse, they can indicate that there may be an underlying addiction, especially if the person experiencing these symptoms consumes morphine.

Side Effects of Morphine

Morphine can cause several side effects, even when used as prescribed. Morphine side effects are mainly related to the effect that morphine has on suppressing the neurological system. These side effects can include:

  • Sleepiness
  • Disorientation
  • Injuries from being unable to detect pain
  • Constipation
  • Nausea
  • Decreased rate of breathing

The most serious side effect that morphine can cause is the decreased rate of breathing. When taken as prescribed, this effect is rarely a concern, but may still affect some people. If someone who is taking morphine starts breathing less than eight times a minute, call 911 for emergency medical assistance.

Side Effects of Long-Term Morphine Abuse

With morphine, long-term side effects are typically not serious but can be in some cases. The main side effects of long-term morphine use include chronic constipation, excessive sweating, swelling, drowsiness and decreased sex drive. If morphine is used in a greater amount than it is prescribed, there is always a danger of an overdose occurring.

Signs of Morphine Overdose

One of the dangers of using morphine is the possibility of an overdose occurring. It is important to be able to recognize the signs of a morphine overdose. These signs include:

  • Decreased rate of breathing
  • Delirium
  • Low blood pressure
  • Low heart rate
  • Decreased temperature
  • Complete cessation of breathing

If you or someone you know may be experiencing any of these overdose symptoms, you should immediately call emergency services using 911.

If you or a loved one live with a morphine addiction, contact The Recovery Village Ridgefield to speak with a representative about how addiction treatment can help you. The Recovery Village Ridgefield uses individualized treatment programs to address addiction and any co-occurring mental health disorders. You deserve a healthier future, call today.


Medscape. “Morphine (Rx).” November 2018. Accessed May 2, 2019.

National Center for Biotechnology Information. “Clinical Guidelines for Withdrawal Management and Treatment of Drug Dependence in Closed Settings.”  2009. Accessed May 1, 2019.

Dixon, David W. “Opioid Abuse.” Medscape, June 21, 2018. Accessed May 1, 2019.

O’Mally, Gerald F. & O’Mally, Rika. “Opioid Toxicity and Withdrawal.” Merck Manuals, March 2018. Accessed May 1, 2019.

Medical Disclaimer: The Recovery Village aims to improve the quality of life for people struggling with a substance use or mental health disorder with fact-based content about the nature of behavioral health conditions, treatment options and their related outcomes. We publish material that is researched, cited, edited and reviewed by licensed medical professionals. The information we provide is not intended to be a substitute for professional medical advice, diagnosis or treatment. It should not be used in place of the advice of your physician or other qualified healthcare provider.