If you or a loved one has been prescribed an opioid, it is important to learn all you can. Understanding prescription opioids starts with a careful review of the facts.

What are prescription opioids?

Prescription opioids are medicines used to treat moderate to severe pain, like you might experience as the result of an accident, surgery or cancer.1,2 For years they have been considered a key component of pain management, and in recent months identified by the World Health Organization as an “essential medicine” for ICU patients suffering with COVID-19.3,4 Though they are used to address critical medical needs, prescription opioids are also known for their potentially serious, even deadly side effects.1

What are some commonly prescribed opioids?

A number of different types and brands of prescription opioids for pain are currently available, including5:

  • hydrocodone (Vicodin®, Norco®, Zohydro®)
  • oxycodone (OxyContin®, Percocet®, Percodan®)
  • codeine
  • morphine (Avinza®, Duramorph®, MS Contin®)
  • fentanyl (Actiq®, Duragesic®, Sublimaze®)
  • hydromorphone (Dilaudid®)
  • oxymorphone (Opana®)
  • buprenorphine (Butrans®, Belbuca®)

These medications are prescribed in different strengths and can be taken in different ways.6

How are prescription opioids taken?

The way prescription opioids are taken depends on the patient, the situation and the type and level of pain experienced.6 Pills or other oral solids are by far the most common forms, representing 96 percent of opioids taken home from the pharmacy.7 Other patients may take home a syrup or transdermal patch.7

How do prescription opioids work?

Opioids attach to and activate opioid receptors on nerve cells in many areas of the brain, spinal cord and other organs, including the lungs.1,8 When this happens, opioids can block pain messages from the brain to the body.1 The short-term effects of prescription opioids are pain relief, relaxation and an overall sense of well being.1 Prescription opioids can also have problematic side effects, including1:

  • drowsiness/sedation
  • confusion
  • nausea
  • constipation
  • slowed breathing

What is the most serious side effect of prescription opioids?

All side effects of medication prescription opioids should be taken seriously, but slowed breathing is of particular concern because it can cause hypoxia.1 Hypoxia is a condition that can occur when too little oxygen reaches the brain.1 The result of this lack of oxygen—coma, permanent brain damage and/or death—is what doctors mean when they use the term “overdose.”1 If your doctor prescribes you an opioid pain reliever, be sure to ask about overdose reversal medication, such as Kloxxado™ (naloxone HCl) Nasal Spray 8 mg.9 Kloxxado™ can block the effects of opioid medications, helping to restore breathing and save lives in emergency situations.9

Why are prescription opioids associated with addiction?

If you take a prescription opioid for an extended period of time, your body can begin to adapt to the medicine.10 When this happens, it might not work as well as it once did.10 Plus, you may need more and more of the medicine to achieve an acceptable level of pain relief.10 This phenomenon is called tolerance.10 Long-term use of prescription opioid pain medications increases the risk of tolerance, which can lead to dependence and addiction.10

How should I take prescription opioids?

When used under a doctor’s supervision, opioid medications can be an important option for pain management—in spite of their risks.11 When and if your doctor prescribes you an opioid pain medication, keep the following in mind:

  • Your medical history—Remind your doctor of all of your medical conditions.11 Sleep apnea, obesity, anxiety or depression and/or fibromyalgia can increase your risk of a bad reaction.11 You’ll also want to be sure your doctor is aware of any mental health and substance misuse problems you currently have or have had in the past, as these may increase your risk of opioid misuse, addiction and/or overdose.11
  • Your other medications—Make sure you tell your doctor and pharmacist about all of the medications you are taking, including over-the-counter remedies and supplements.11 If you can, have all of your prescriptions filled at the same pharmacy.11 Many are set up to alert the pharmacist to potentially dangerous drug interactions among the medicines prescribed for an individual patient.11
  • The doctor or pharmacist’s instructions—Read the instructions and warnings on the safety information sheet that comes with your prescription.11 Follow the instructions exactly and contact your doctor if you have questions or problems.11
  • Possible side effects—If your opioid medication is causing side effects—drowsiness/sedation, confusion, nausea, constipation or slowed breathing—tell your doctor right away.11
  • Overdose reversal medication—According to the National Safety Council, people are more likely to die from accidental opioid overdose than in a car crash.12 If you are prescribed opioid pain medication, ask your doctor to prescribe an overdose reversal medication such as Kloxxado™.9 In an emergency, Kloxxado™ can block the effects of opioids and quickly restore normal breathing to a person whose breathing has slowed or stopped.9 When you receive your overdose reversal medication, make sure the people you live with know where you keep it how to give it in the event of an emergency. Remind those around you to immediately call 911 to get emergency assistance as soon as Kloxxado™ is administered.9
  • Safe disposal of excess medication—When you no longer need opioid pain relief, you will need to safely dispose of any extra medicine.11 Many national chain pharmacies, including CVS, Walgreens and Walmart, have safe medication disposal programs.13-15 For information about safe disposal of opioid medications, talk with your doctor or pharmacist.11

Kloxxado™ is a trademark of Hikma Specialty USA Inc.

All other trademarks and registered trademarks are the property of their respective owners.

Important Safety Information About Kloxxado™ (naloxone HCl) Nasal Spray


Hypersensitivity to naloxone hydrochloride or to any of the other ingredients

Warnings and Precautions

  • Use Kloxxado™ right away if you suspect an opioid overdose emergency, even if you are not sure, because an opioid overdose emergency can cause severe injury or death. Signs and symptoms of an opioid overdose emergency may include:
  • Unusual sleepiness; you are not able to awaken the person with a loud voice or by rubbing firmly on the middle of their chest (sternum).
  • Breathing problems, including slow or shallow breathing in someone difficult to awaken or who looks like they are not breathing.
  • The black circle in the center of the colored part of the eye (pupil) is very small (sometimes called “pinpoint pupils”) in someone difficult to awaken.
  • Family members, caregivers or other people who may have to use Kloxxado™ in an opioid overdose emergency should know where Kloxxado™ is stored and how to give Kloxxado™ before an opioid overdose emergency happens.
  • Get emergency medical help right away after using the first dose of Kloxxado™. Rescue breathing or CPR (cardiopulmonary resuscitation) may be needed while waiting for emergency medical help.
  • The signs and symptoms of an opioid overdose emergency can return after Kloxxado™ is given. If this happens, give another dose after 2 to 3 minutes, using a new Kloxxado™ device, alternating nostrils, and watch the person closely until emergency medical help arrives.
  • Do not use Kloxxado™ if you are allergic to naloxone hydrochloride or any of the ingredients in Kloxxado™.
  • Kloxxado™ can cause sudden and severe opioid withdrawal, the symptoms of which may include body aches, diarrhea, increased heart rate, fever, runny nose, sneezing, goosebumps, sweating, yawning, nausea or vomiting, nervousness, restlessness or irritability, shivering or trembling, stomach cramps, weakness and increased blood pressure.
  • In infants, opioid withdrawal may be life-threatening if not recognized and properly treated. Infants going through opioid withdrawal may have seizures, cry more than normal, and have increased reflexes.
  • Tell your doctor about all of your medical conditions before using Kloxxado™, including if you have heart problems, are pregnant or plan to become pregnant.
  • Tell your doctor about all of the medicines you take, including prescription and over-the-counter medicines, drugs, vitamins and herbal supplements.

Side Effects

The following serious side effect is discussed in the full Prescribing Information for Kloxxado™:

  • Sudden and Severe Opioid Withdrawal

Symptoms of sudden and severe opioid withdrawal resulting from the use of Kloxxado™ in someone regularly using opioids include: body aches, diarrhea, increased heart rate, fever, runny nose, sneezing, goosebumps, sweating, yawning, nausea or vomiting, nervousness, restlessness or irritability, shivering or trembling, stomach cramps, weakness and increased blood pressure.

Infants may have seizures, cry more than normal and have increased reflexes.

Some people may become aggressive after abrupt reversal of opioid overdose.

In two clinical studies, a total of 47 healthy adult volunteers were exposed to a single dose of Kloxxado™, one spray in one nostril. Side effects were reported in two subjects for each of the following: abdominal pain, asthenia, dizziness, headache, nasal discomfort, and presyncope.

These are not all of the possible side effects of Kloxxado™. Contact your doctor for medical advice about side effects.

Pregnancy, Infancy and Breastfeeding, Children

Tell your doctor if you are pregnant or plan to become pregnant. If you are pregnant and opioid dependent, use of Kloxxado™ may cause withdrawal symptoms in you and your unborn baby. A healthcare provider should monitor you and your unborn baby right away after you use Kloxxado™.

There is no information regarding the presence of naloxone in human milk, the effects of naloxone on the breastfed infant or on milk production.

If the primary concern is an infant at risk of an overdose, consider whether other naloxone-containing products may be more appropriate.

Kloxxado™ nasal spray is safe and effective in children for known or suspected opioid overdose.

Dosage and Administration

Do not attempt to prime or test-fire the device. Each Kloxxado™ Nasal Spray contains only 1 dose of medicine and cannot be reused. Read the “instructions for use” at the end of the Prescribing Information and Medication Guide for detailed information about the right way to use Kloxxado™ Nasal Spray.

Storage and Handling

Store Kloxxado™ at room temperature between 59 F to 77F (15C to 25C). Kloxxado™ may be stored for short periods between 39°F to 104°F (4°C to 40°C). Do not store above 40ºC (104ºF). Do not freeze Kloxxado™. Keep Kloxxado™ in its box until ready to use. Protect from light. Replace Kloxxado™ before the expiration date on the box. Keep Kloxxado™ and all medicines out of the reach of children.

Please see the full Prescribing Information and Medication Guide for Kloxxado™ for complete product details.

NOTE: This article was not written by a medical professional and is not intended to substitute for the guidance of a physician. These are not Hikma’s recommendations, but rather facts and data collected from various reliable medical sources. For a full list of resources and their attributing links, see below.


  1. Prescription Opioids DrugFacts. National Institute on Drug Abuse website. Available at: https://www.drugabuse.gov/publications/drugfacts/prescription-opioids. Accessed February 23, 2021.
  2. Prescription Opioids. Centers for Disease Control and Prevention website. Available at: https://www.cdc.gov/drugoverdose/opioids/prescribed.html. Accessed February 23, 2021.
  3. Timeline of Selected FDA Activities and Significant Events Addressing Opioid Misuse and Abuse. US Food & Drug Administration website. Available at: https://www.fda.gov/drugs/information-drug-class/timeline-selected-fda-activities-and-significant-events-addressing-opioid-misuse-and-abuse. Accessed February 23, 2021.
  4. Essential Medicines List for Management of Patients Admitted to Intensive Care with Suspected or Confirmed COVID-19 Diagnosis, 24 March 2020. Pan American Health Organization/World Health Organization website. Available at: https://iris.paho.org/handle/10665.2/52191. Accessed February 23, 2021.
  5. Data on file: Hikma internal analysis, IQVIA NSP Audit, USC 3 = Analg Narc, most recent 12 months. Accessed February 15, 2021.
  6. What Are Opioids. American Society of Anesthesiologists website. Available at: https://www.asahq.org/madeforthismoment/pain-management/opioid-treatment/what-are-opioids/#anchor5. Accessed February 23, 2021.
  7. Data on file: Hikma internal analysis, IQVIA NSP Audit, USC 3 = Analg Narc, most recent 12 months. Accessed February 15, 2021.
  8. How opioids cause dangerous breathing problems. Science Daily website. Available at: https://www.sciencedaily.com/releases/2015/12/151217130559.htm. Accessed February 23, 2021.
  9. Kloxxado™ (naloxone hydrochloride) nasal spray [prescribing information]. Columbus, OH: West-Ward Columbus, Inc.; 2020.
  10. Treating pain: When is an opioid the right choice? Mayo Clinic website. Available at: https://www.mayoclinic.org/diseases-conditions/prescription-drug-abuse/in-depth/when-is-opioid-right-choice/art-20346884. Accessed February 23, 2021.
  11. How to use opioids safely. Mayo Clinic website. Available at: https://www.mayoclinic.org/diseases-conditions/prescription-drug-abuse/in-depth/how-to-use-opioids-safely/art-20360373. Accessed February 23, 2021.
  12. For the First Time, We’re More Likely to Die from Accidental Opioid Overdose Than Motor Vehicle Crash. National Safety Council website. Available at: https://www.nsc.org/newsroom/for-the-first-time,-were-more-likely-to-die-from. Accessed February 23, 2021.
  13. Safer Communities/Who’s taking your pills? CVS website. Available at: https://www.cvs.com/content/safer-communities-locate. Accessed February 23, 2021.
  14. Safe medication disposal. Walgreens website. Available at: https://www.walgreens.com/topic/pharmacy/safe-medication-disposal.jsp. Accessed February 23, 2021.
  15. How to dispose of medications safely. Walmart website. Available at: https://www.walmart.com/ideas/health-wellness-center/how-to-dispose-of-medications-safely/201837. Accessed February 23, 2021.