Table of ContentsView AllTable of ContentsWhat Is Naloxone?How Does Naloxone Work?What Is Naltrexone?Dosing ComparisonComparing EfficacyWhat Causes a Drug Overdose?Side EffectsWhen to AvoidInteractionsFrequently Asked Questions
Table of ContentsView All
View All
Table of Contents
What Is Naloxone?
How Does Naloxone Work?
What Is Naltrexone?
Dosing Comparison
Comparing Efficacy
What Causes a Drug Overdose?
Side Effects
When to Avoid
Interactions
Frequently Asked Questions
Naloxone is an emergency drug, while naltrexone is used with social support to help people who quit street drugs and alcohol. Naloxone is a short-term drug that can be given to anyone to cope with an opiate overdose and restore breathing.
On the contrary, naltrexone can only be used after quitting the drugs and alcohol in the presence of a healthcare provider. Common brand names of naloxone are available, such as Zimhi, and for naltrexone, there is Vivitrol.
Opiate overdose is one of the leading causes of drug overdose deaths. In 2021, more than 100,000 people died from an overdose. Most of these deaths involved synthetic opioids, taking the lives of 70,601 people in 2021.
Read below to find how these naloxone vs. naltrexone differ and how they can help prevent a life from drug abuse and overdoses.
Marvin Samuel Tolentino Pineda / Getty Images
Naloxone is an opioid antagonist. It is a life-saving drug that can quickly reverse the powerful effects of opioids during an overdose.
It is administered in various ways, such as intramuscular injection or nasal spray.
Naloxone is FDA-approved for the following indications:
Naloxone can also used alongsidebupropion, a partial opioid agonist, as a combinational medication to treat opioid dependence.
Buprenorphine alone and the combination of buprenorphine and naloxone prevent withdrawal symptoms when someone stops taking opioids.
Everyone who overdoses on prescription opioids or a recreational drug can use naloxone. Examples of opioids include heroin, Fentora (fentanyl),OxyContin (oxycodone),Vicodin (hydrocodone), codeine, and morphine.
Naloxone does not affect or cause harm to people without an opioid in their system and has another medical emergency, such as a diabetic coma or cardiac arrest. Administer naloxone to save a life even when unsure about an opioid overdose.
In most states, you can get naloxone over-the-counter (OTC) from the pharmacy without a prescription. It is also possible to get naloxone from other health clinics.
When an opioid overdose is suspected, naloxone hydrochloride should be administered as soon as possible to reverse the effects of an overdose.
Naloxone does not affect someone who does not have opioids in their system. It is not a treatment for opioid use disorder.
The FDA has approved two dosage forms for Naloxone: injectable and prepackaged nasal spray:
Naloxone can be given to people of all ages, including adults, infants, children, and seniors.
Naltrexone is used in people who have stopped drinking alcohol and are not actively taking it anymore.
It also helps people with opioid dependence after opioid addiction treatment (also called opioid detoxification), along with counseling and social support.
Note that naltrexone should not be used in people still drinking and using opioids or other street drugs.
Other off-label uses of naltrexone may include pain, reduced inflammation, and treatment of conditions and diseases, including immune dysfunction and cancer.
It is also used in dermatology for treating trichotillomania (an urge to pull out one’s hair) and different types of pruritus(itching).
Like naloxone, bupropion is also in tandem with naltrexone.
However, in this case, bupropion and naltrexone are used together with a diet/exercise to help adults with obesity or overweight status with weight-related medical problems lose weight and stop excess weight from returning.
How Does Naltrexone Work?
Naltrexone works on opiate receptors to block the euphoric (feeling of excitement and happiness) and sedative effects of opioids and alcohol to reduce and suppress opioid cravings.
It is not addictive and does not cause withdrawal symptoms after discontinuation.
Regarding Naltrexone’s affiliated brand names, it is marketed under Vivitrol. Vivitrol is an extended-release (which releases the drug in continued doses over some time) injection for subcutaneous use (under the skin).
In comparison, generic naltrexone is available in tablet form.
The following outlines basic dosing guidelines for the use of naltrexone and naloxone. However, know that your specific dose may vary.
Recommended dosage of naloxone:
Each unit of nasal spray dosage form contains 4 milligrams (mg) of naloxone hydrochloride per device and delivers a single spray containing 4 mg of naloxone hydrochloride:
Another dosage form of naloxone is 5 mg/0.5 milliliters (mL) naloxone hydrochloride solution in a single-dose, prefilled syringe for intramuscular or subcutaneous use only.
Recommended dosage of injectable naltrexone:
Recommended dosage of oral naltrexone:
Naloxone is a short-acting drug used to reverse the effects of an opioid overdose. It is the most effective drug and improves breathing and other symptoms in two to three minutes in the affected person.
The FDA is working with other federal, state, and local officials to help increase the availability of naloxone to combat opioid overdoses.
While naltrexone is a drug for suppressing opioid use disorder and alcohol intake craving, counseling, and social support, it is a prescription and long-acting treatment.
Clinical studies have shown that naltrexone helps people to remain abstain from alcohol for a longer duration than placebo.
Drug Overdose: Causes & Factors
An overdose is a toxic drug or substance that interferes with the brain and body’s functioning ability. The deaths from drug overdose remain a leading cause of death in the United States.
The majority of overdose deaths involve opioids. Deaths involving opioids such as fentanyl, cocaine, and methamphetamine have increased in recent years.
The number of people who died from a drug overdose in 2021 was over six times the number in 1999.
Certain factors or causes can increase the risk of an opiate overdose. Some of these factors include:
Side Effects & Safety
Naltrexone and naloxone are relatively effective and safe drugs for emergencies. However, like all drugs, they do carry the potential for common, minor side effects and more severe ones.
Be sure to tell your healthcare provider if you have any side effect that bothers you or does not go away.
Common Side Effects
Common side effects associated with the use of naloxone include:
In comparison, common side effects associated with the use of naltrexone include:
Severe Side Effects
Naloxone may cause serious side effects, including:
Call your healthcare provider or ask for immediate medical help if you or anyone develop these symptoms.
Comparatively, naltrexone has some severe side effects that need medical attention, including the onset of depression.
The depressed mood needs help from family, friends, and a healthcare provider. A depressed person may have the following symptoms such as:
Naltrexone is also associated with pneumonia. Pneumonia is associated with shortness of breath, wheezing, or coughing that does not go away.
Allergic reactions to the drug cause symptoms such as:
Finally, naltrexone may cause liver damage if taken in higher doses, including symptoms such as stomach area pain, dark urine, yellowing of the whites of the eyes, and tiredness.
Who Should Avoid Naloxone or Naltrexone?
Closely monitor people taking naltrexone drugs for the following problems:
Regarding using naltrexone and naloxone in pregnant and breastfeeding people, those people should use them with care to avoid adverse effects.
Potential for Interaction
Always mention all the drugs you are taking to your healthcare provider before starting treatment with any drug.
Naloxone is an immediate response medicine and is usually safe to administer and does not interact with most drugs.
In comparison, Naltrexone antagonizes (cancels) the effects of opioid-containing medicines, such as cough and cold medication, antidiarrheal preparations, and opioid analgesics, such as Methadose (methadone). These medicines may not be helpful when taking Naltrexone therapy.
Do not take any opioid medications or use opioid street drugs during the past seven to 10 days of treatment with naltrexone.
Summary
From 1999-2021, nearly 645,000 people died from an overdose involving any opioid, including prescription and illegal opioids.
Naloxone and naltrexone are two opiate antagonist drugs that can play a part. These drugs belong to the same class but are used for different purposes.
Naloxone is an emergency help given to adults and children experiencing an overdose. It works within a few minutes to improve the symptoms.
Call for emergency help after giving naloxone. Carry naloxone or keep it at home if you or someone else is at increased risk for opioid overdose or struggling with OUD.
It is not easy to struggle against opioid misuse. Medications, social help, family and friends support, and professional help can play a part. Never be afraid to talk about it and ask for help.
In some states, you can get naloxone from a pharmacist without a prescription. It is also possible to get naloxone free of charge from community-based distribution programs, local public health groups, or local health departments.Naltrexone is part of a comprehensive treatment plan, which includes counseling and other behavioral therapies to overcome alcohol and opiate misuse. It is available only on prescription from a healthcare licensed healthcare provider.
In some states, you can get naloxone from a pharmacist without a prescription. It is also possible to get naloxone free of charge from community-based distribution programs, local public health groups, or local health departments.
Naltrexone is part of a comprehensive treatment plan, which includes counseling and other behavioral therapies to overcome alcohol and opiate misuse. It is available only on prescription from a healthcare licensed healthcare provider.
Store naloxone injection and nasal spray at room temperature (between 68 and 77 degrees F).Store naltrexone injection in the refrigerator between 36 and 46 degrees F. Unrefrigerated naltrexone can be kept at room temperature for seven days. Do not refrigerate it.
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