Opioid Side Effects

Opioids are best known for their pain-relieving and euphoric effects, but the powerful drugs have a host of side effects. Opioids frequently cause nausea, vomiting, constipation and severe itching. Long-term use can lead to dependence, addiction and numerous physical complications, including overdose and death.
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Opioids are potent drugs that can dull sensations of pain and trigger intense feelings of pleasure. The drugs can also produce a range of unwanted effects, ranging from nausea and constipation to extreme sedation, breathing problems and even death.

Opioids, which include prescription painkillers and the street drug heroin, are highly addictive. A person can become physically dependent on an opioid drug within a couple of weeks of consistent use.

As prescriptions for opioid painkillers have soared over the last two decades, so have rates of opioid addiction. In 2016, more than 42,000 people died from an opioid overdose, and an estimated 2.1 million Americans were addicted to opioids.

Approximately 40 percent of the 42,249 opioid overdose deaths in 2016 involved a prescription opioid.

Short-Term Effects of Opioids

Morphine, oxycodone, hydrocodone and other opioids can cause a wide range of short-term effects. Nausea, vomiting, dizziness and sedation are among the most common reactions to the drugs.

Side effects can develop even when the drugs are used as directed.

Other short-term effects of opioids include:

  • Feelings of euphoria
  • Dry mouth
  • Headache
  • Flushing
  • Mental fog
  • Constipation
  • Drowsiness
  • Itching
  • Respiratory depression
  • Lethargy

While opioids can cause allergic reactions, life-threatening anaphylactic reactions to opioids are rare.

The intense itching that many people experience while taking opioids is actually considered a “pseudo-allergic” reaction. Pseudo-allergies can mimic immune reactions, but they aren’t actually caused by an antibody response like an actual allergy.

According to a 2011 study in the medical journal Cell, itching occurs because opioids activate special “itch-specific” receptors in the spinal cord.

Long-Term Effects of Opioids

Chronic or long-term use of opioids can lead to a number of serious side effects and complications.

Other long-term effects of opioid use include:

  • Addiction
  • Irregular heart beat
  • Increased risk of heart attack
  • Depression
  • Constipation
  • Severe abdominal pain
  • Hormonal problems
  • Weak bones
  • Increased pain

Opioid-induced constipation is a common complication in people who use opioid medications. Severe cases can cause considerable pain, blockage and even perforation of the intestines. A bowel perforation is a life-threatening emergency that requires surgery.

People who used opioids chronically can also develop narcotic bowel syndrome. The condition is characterized by acute and worsening abdominal pain. Other symptoms include constipation, bloating and nausea.

The syndrome appears to be closely related to opioid-induced hyperalgesia, a phenomenon whereby people become overly sensitive to pain as a result of their chronic use of opioids. Both conditions usually resolve when opioids are discontinued.

Signs and Symptoms of Opioid Addiction

Continuous use of opioids almost always leads to physical dependence. When you’re opioid dependent, you’ll have a high tolerance and need increasingly larger amounts the drug to achieve the desired effects. You’ll also become ill when you stop taking the drug or reduce your normal dose.

Chronic opioid use can also cause changes in the brain, resulting in an opioid addiction. Opioid addiction is characterized by uncontrollable cravings and compulsive use of the drug despite its negative impact on your life.

A person who is addicted to opioids may try to hide their problem from others, but there are usually physical and behavioral warning signs.

Some common red flags that may signal an opioid addiction include:

  • Drastic changes in behavior or habits
  • Changes in appearance
  • Unusual sleepiness
  • Unexplained weight loss
  • Scratching or picking skin
  • Droopy eyes
  • Difficulty concentrating
  • Lack of Motivation
  • Loss of interest in activities once enjoyed
  • Secrecy
  • Stealing

While opioid addiction is a chronic and relapsing disease, treatment can help. Opioid addiction treatment offers safe detox and coping strategies for dealing with triggers and avoiding relapse. Medications, in combination with behavioral therapy and counseling, are a mainstay of opioid rehab.

Signs and Symptoms of an Opioid Overdose

Because opioids depress the central nervous system, high doses can dangerously slow or stop your breathing. This can cut off blood flow to your brain and kill you. Pauses in breathing are particularly common at night but can occur at any time.

Older people and individuals with sleep apnea, heart problems, lung disease and other medical conditions are more vulnerable to developing respiratory distress while taking opioids. Mixing opioids with other drugs or alcohol also increases the risk of an opioid overdose.

Signs and symptoms of an opioid overdose include:

  • Excessive sleepiness
  • Breathing difficulty
  • Slowed or stopped breathing
  • Snoring or gurgling sounds
  • Pinpoint pupils
  • Cold, clammy skin
  • Weak or limp muscles
  • Blue or grayish skin and dark lips or fingernails
  • Loss of consciousness or coma

People who inject opioids are more likely to overdose. A person’s risk of overdose is also higher after a period of abstinence — such as after being incarcerated or following detox — because of a reduced tolerance.

Certain opioids, including fentanyl and carfentanil, can be deadly in very tiny doses. Heroin is frequently contaminated with fentanyl and carfentanil and can cause a fatal overdose in minutes. The potent opiods have also been showing up in counterfeit prescription painkillers and in cocaine.

Opioid Withdrawal Symptoms

If you suddenly stop taking an opioid or lower your dose after a long period of use, you may develop uncomfortable, flu-like withdrawal symptoms.

Symptoms of opioid withdrawal:

  • Watery eyes and runny nose
  • Sneezing
  • Yawning
  • Sweating
  • Chills
  • Body aches
  • Abdominal cramps
  • Nausea and vomiting
  • Diarrhea
  • Loss of appetite
  • Fast heart rate
  • Elevated blood pressure
  • Rapid breathing
  • Weakness
  • Irritability and anxiety
  • Insomnia
  • Depression

The intensity and duration of opioid withdrawal may vary depending on which drug you were taking, how much you were taking and how long you were using it.

With short-acting opioids, such as oxycodone or hydrocodone, symptoms typically arise within six to eight hours after the last dose. Symptoms typically peak within two to three days and resolve within a week. Withdrawal from longer-acting opioids, such as methadone or OxyContin, may not begin for 24 to 72 hours and will peak within a week to 10 days. Symptoms can last up to three weeks.

A medical detox can ease the pain of opioid withdrawal. At a detox center, you’ll receive medications that diminish withdrawal symptoms, and staff will carefully monitor your condition. Withdrawal is never easy, but with support, you can take this important first step in the process of recovery.

Medical Disclaimer: DrugRehab.com 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.

Amy Keller, RN, BSN
Content Writer, DrugRehab.com
As a former journalist and a registered nurse, Amy draws on her clinical experience, compassion and storytelling skills to provide insight into the disease of addiction and treatment options. Amy has completed the American Psychiatric Nurses Association’s course on Effective Treatments for Opioid Use Disorder and continuing education on Screening, Brief Intervention and Referral to Treatment (SBIRT). Amy is an advocate for patient- and family-centered care. She previously participated in Moffitt Cancer Center’s patient and family advisory program and was a speaker at the Institute of Patient-and Family-Centered Care’s 2015 national conference.
Kim Borwick, MA
Editor, DrugRehab.com

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