What are opioids?
Opioids (sometimes called narcotics) are a class of drugs that are chemicals — natural or synthetic — that interact with nerve cells that have the potential to reduce pain. Healthcare providers typically prescribe opioids to manage moderate to severe pain.
However, opioids can become addictive because they not only dull pain but produce a sense of euphoria. This, combined with tolerance build (needing to increase doses to produce the same effect) can lead to opioid use disorder. Because of this, providers have modified their prescribing practices to reduce the length and strength of opioids to try to prevent addiction.
What is the difference between opiates and opioids?
An opioid is a substance that can be derived from the from the poppy plant, be synthetic or be semi-synthetic, meaning the active ingredients are created chemically in a lab. Common opioids include morphine, oxycodone, OxyContin, hydrocodone, fentanyl and others.
All opiates are opioids, but not all opioids are opiates. However, opioids and opiates have the same effects on your body because they have similar molecules, and they both have high addiction potential.
What are opioids approved for?
Prescription opioids are approved for managing moderate to severe pain. This can include:
- Some types of acute pain (sudden and short-term).
- Cancer-related pain.
- Post-surgical pain.
- Vascular pain, such as acute sickle-cell crisis.
The U.S. Food and Drug Administration (FDA) has also approved the use of some opioids to treat intense coughing and chronic diarrhea. Loperamide is an opioid healthcare providers use to treat diarrhea and irritable bowel syndrome (IBS). Opioids such as codeine and dextromethorphan are useful as cough suppressants.
How do opioids work?
"Opioid" is an umbrella term that represents all compounds that bind to opioid receptors. Opioid receptors are found throughout your central and peripheral nervous systems, as well as your gastrointestinal (GI) tract. These receptors regulate many body functions, including:
- Gastrointestinal functions.
- Breathing (respiration).
Once activated, opioid receptors initiate a cascade of chemical reactions that ultimately modulate the transmission of pain signals. Opioids also cause neurons that produce dopamine, the neurotransmitter that plays a role in how we feel pleasure, to fire more frequently. This creates feelings of euphoria (intense happiness).
Some opioids are used to stop diarrhea by slowing gastric motility — the process by which food travels through your digestive tract via a series of muscular contractions. This allows more time for absorption of the food in your system.
What are the types of opioids?
There are over one hundred different types of prescription opioids. The most commonly prescribed opioids and some of the most common brand names include:
- Hydrocodone (Vicodin®).
- Oxycodone (OxyContin®, Percocet®).
- Oxymorphone (Opana®).
- Morphine (Kadian®, Avinza®).
Heroin is a morphine derivative drug that’s exclusively used for recreational purposes and is illegal.
What should I tell my healthcare provider before taking opioids?
In a discussion with your healthcare provider about whether you need to take opioids, you should discuss the following topics:
- Whether there are other medicines or therapies that might treat your pain.
- The risks and benefits of taking opioids.
- Your medical history.
- If you or anyone in your family has a history of substance use or addiction to drugs or alcohol.
- Any other medicines and supplements you’re taking, which may interact with the opioid.
- How much alcohol you drink.
- If you’re pregnant or planning to become pregnant.
- If you use marijuana/cannabis (prescription or otherwise).
- If you use any street drugs.
You also need to tell your provider about any medical conditions you have. Opioids can worsen the effects of certain conditions and vice versa. For example:
- People with lung conditions and breathing issues may not be able to manage the respiratory depression caused by opioids.
- If people with liver or kidney issues take opioids, they may have poor excretion and metabolism, which may result in the accumulation of harmful byproducts.
- People with certain adrenal gland and thyroid issues may be more sensitive to opioids.
Why are opioids addictive?
The main reason opioids have a high addiction potential is because they not only relieve pain but create a sense of euphoria (intense happiness), which many people find pleasurable.
People who use opioids regularly soon develop tolerance to these effects. They may then use more and more of the drug in an attempt to get the original intensity of pain relief and euphoria. Chronic use or misuse of opioids can lead to psychological and physical dependence.
People are psychologically dependent when a drug is so central to their thoughts, emotions and activities that the need to continue its use becomes a craving or compulsion despite negative consequences.
With physical dependence, your body has adapted to the presence of the drug, and withdrawal symptoms happen if you suddenly stop taking the drug or you take a reduced dosage.
People who are physically dependent on opioids experience withdrawal symptoms when they stop taking the drug. These symptoms are often unpleasant, so they may be more likely to take more of the drug to stop the withdrawal symptoms.
Does everyone who is prescribed an opioid become addicted?
No, not everyone taking a prescription opioid becomes addicted to them. When prescription instructions are carefully followed, the chances of becoming addicted are decreased.
Opioids are useful for treating acute pain through short-term use. However, when a prescription drug is used outside of the instructions or for chronic pain, the risk of developing opioid use disorder increases.
Frequently Asked Questions
How should I take prescribed opioids?
You should always be careful when taking any prescribed medication, but you need to take extra care when taking prescribed opioids. Helpful tips include:
- Take your medication exactly as prescribed by your healthcare provider — do not take extra doses.
- Check the instructions every time you take a dose.
- Do not break, chew, crush or dissolve opioid pills.
- Do not drive or use any machinery that may injure you or others, especially when you first start the medication. Opioids can cause drowsiness.
- Contact your provider if you have side effects.
- If you can, use the same pharmacy for all your medications. The pharmacy's computer system will alert the pharmacist if you’re taking two or more medicines that could cause a dangerous interaction.
If you feel that you’re dependent on opioids or your prescribed dosage isn’t helping you manage your symptoms, do not take more than your recommended dosage and talk with your healthcare provider immediately.
Never share your opioid medication with someone else or sell your medication. Always store it in a safe place away from children and pets.
What are the side effects of opioids?
Common side effects of opioids include:
- Drowsiness (sedation).
- Nausea and vomiting.
- Physical dependence — Dependence often manifests with withdrawal symptoms when opioids are discontinued or decreased.
- Tolerance — As you take repeated doses of opioids, you require increased medication to experience the same effect of pain relief.
- Respiratory depression — This can occur in healthy people, especially with higher doses. However, people with COPD, asthma or other lung conditions may be even more susceptible to fatal respiratory impairment.
Uncommon side effects of opioids include:
- An increased sensitivity to feeling pain and extreme response to pain (hyperalgesia). Chronic use of opioids can lead to this.
- Delayed gastric emptying (the process by which the contents of your stomach are moved into your small intestine).
- Muscle rigidity.
- Immune system and hormonal dysfunction.
- Quick, involuntary muscle jerks (myoclonus).
- Itchy skin (pruritus).
- Dry mouth (xerostomia).
What are the long-term effects of opioids?
Long-term side effects from chronic opioid use include:
- Chronic constipation.
- Sleep-disordered breathing (SDB).
- Increased risk of bone fractures.
- Hypothalamic-pituitary-adrenal dysregulation.
- Increased risk of overdose.
What’s known about opioids and overdose?
An overdose happens when too much of a drug is taken and harms your body. When too many opioids are taken, your breathing can slow and stop. Opioid overdoses can be nonfatal or they can result in death. People who have opioid use disorder are more likely to experience an overdose.
If you take opioids exactly as prescribed by your provider, it’s very unlikely that you’ll experience an opioid overdose.
An opioid overdose can happen for a variety of reasons, including if you:
- Take an opioid to get high.
- Take an extra dose of a prescription opioid or take it too often (either accidentally or on purpose).
- Mix an opioid with other medications, illegal drugs or alcohol. An overdose can be fatal when mixing an opioid and benzodiazepines — medications prescribed to treat anxiety and insomnia. Common benzodiazepines include diazepam (Valium®), alprazolam (Xanax®) and clonazepam (Klonopin®).
- Take an opioid medication that was prescribed for someone else. Children are especially at risk of an accidental overdose if they take medication not intended for them.
Immediate action is needed to help someone experiencing an opioid overdose. Naloxone (commonly known by the brand name Narcan®) is a drug that treats the overdose immediately. Naloxone can reverse the effects of an opioid overdose if it’s given to the person quickly. Medical attention is still urgently needed after naloxone is administered.
In 2019, nearly 50,000 people in the United States died from opioid-involved overdoses. The misuse of and addiction to opioids — including prescription opioids, heroin and synthetic opioids such as fentanyl — is a serious national crisis that affects public health. It’s often referred to as the opioid epidemic or opioid crisis.
What forms do opioids come in?
Prescription opioids come in various forms, including:
- Tablets and capsules (oral pills).
- Oral solutions.
- Injected solutions.
What are the dosage strengths of opioids?
Prescribed dosages for opioids vary based on the brand, type and reason for taking the drug.
Healthcare providers measure opioid dosages in morphine milligram equivalents (MME) or morphine equivalent doses (MED), which are values that represent the potency of an opioid dose relative to morphine. MME is intended to help providers make safe, appropriate decisions concerning changes to opioid regimens.
Higher dosages of opioids are associated with a higher risk of overdose and death — even relatively low dosages, like 20 to 40 MME per day, increase the risk.
Dosages at or above 50 MME per day increase risks for overdose by at least two times the risk than someone would have at less than 20 MME per day.
What other medications and substances can interact with opioids?
It’s very important to tell your healthcare provider which medications, supplements and/or other substances you’re taking before starting prescribed opioids.
Drugs and substances that may interact with prescribed opioid medications include:
- Anti-seizure medications, such as carbamazepine.
- Benzodiazepines and sedatives.
- Certain antibiotics, including clarithromycin.
- Certain antidepressants.
- Certain antifungals, including itraconazole, ketoconazole and voriconazole.
- Certain antiretroviral drugs used for HIV, including atazanavir, indinavir, ritonavir and others.
- Medications for sleeping disorders, such as zolpidem.
- Medications used to treat psychiatric disorders, such as haloperidol.
- Muscle relaxants, such as cyclobenzaprine, tizanidine, methocarbamol and baclofen.
- Medications used to treat nerve-related pain, such as pregabalin and gabapentin.
- Marijuana/cannabis (prescription or otherwise).
Can I drink alcohol while on opioids?
Do not drink any alcohol while taking opioids. Drinking alcohol with these medications may make you even more drowsy and increase the risk of other side effects occurring.
Can I take opioids if I’m pregnant or thinking of becoming pregnant?
Healthcare providers generally don’t prescribe opioids to people who are pregnant since the baby can become dependent on opioids. Approximately 50% of babies develop neonatal abstinence syndrome when exposed to opioids while in the uterus.
Babies can then go through drug withdrawal after birth. Babies with neonatal abstinence syndrome may develop the following issues:
- Abnormally rapid breathing (tachypnea).
Do opioids pass into breast milk?
Extreme caution should be used if you’re considering breastfeeding (chestfeeding) while taking opiates. Opiates have the potential to cause life-threatening issues for your baby. They should be taken only under the direction and close supervision of your provider.
Make sure your provider knows you’re breastfeeding, and take the medication exactly as instructed. If you take any of the following prescribed opioids (or any other opioid), talk to your provider about switching to a safer medication:
- Codeine or medicines that contain codeine.
How long do opioids stay in your system?
The amount of time opioids stay in your system can vary greatly. Factors that affect how quickly an opioid leaves your system include:
- The specific drug as well as its formulation.
- Your metabolism rate.
- Your body mass and weight.
- Your body fat content.
- The health of your liver and kidneys.
- Your age.
- How often and how heavy opioid use is.
- The amount of water in your body.
Do opioids cause withdrawal symptoms?
If you take your prescription opioid medication exactly as instructed by your healthcare provider, you shouldn’t experience withdrawal symptoms once you’ve finished your course of medication.
If you misuse opioids and stop or cut back on these drugs after heavy use for a few weeks or more, you’ll likely have withdrawal symptoms, including:
- Runny nose (rhinorrhea).
- Excessive tears in your eyes/watery eyes (lacrimation).
- Hyperventilation (rapid or deep breathing, usually caused by anxiety or panic).
- Abnormally high body temperature (hyperthermia).
- Muscle aches.
The severity of withdrawal symptoms varies from person to person and based on how long you’ve been taking the opioid and the type of opioid.
A note from Cleveland Clinic
Opioids are very powerful drugs that affect your central and peripheral nervous systems. Due to their high addiction potential, it’s essential to make sure you follow your healthcare provider’s instructions for taking the medication. Do not take more than your daily recommended dose. Talk with your healthcare provider as soon as possible if you feel like you’re dependent on opioids or if they’re not working to alleviate your symptoms.
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