9 Opioid Side Effects You Should Know About
Key takeaways:
Opioids are medications that treat pain that can’t be relieved by non-opioid medications. They have many possible side effects.
Common opioid side effects include constipation, nausea and vomiting, and drowsiness. Serious side effects include physical dependence, misuse, and overdose.
You may be able to manage some mild opioid side effects at home. Others may require speaking to your healthcare provider or seeking emergency care.
Table of contents
Opioid medications are pain relievers. They treat pain that can’t be alleviated by non-opioid medications. Examples of opioids include oxycodone (Roxicodone, Oxycontin), tramadol (ConZip, Qdolo), and hydrocodone/acetaminophen.
Opioids are strong pain medications, and they have significant risks to keep in mind.
Opioid side effects at a glance
Some opioid side effects are common. But they may be mild enough to manage at home. These include:
Constipation
Nausea and vomiting
Drowsiness
Dizziness
Itchiness
Other side effects can be more serious. These include:
Increased sensitivity to pain (hyperalgesia)
Withdrawal symptoms when stopping an opioid abruptly
Below, we’ll cover nine important opioid side effects to be aware of. But keep in mind that individual opioids may have slightly different side effects from one another. And everyone responds to opioids differently.
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1. Constipation
Constipation is a common opioid side effect. In fact, it’s the most common side effect of long-term opioid treatment. Opioids cause constipation because they interfere with how well your digestive tract works. This includes slowing down how quickly food and waste move through your body.
You may have constipation immediately after starting opioids, or it can develop after you’ve been taking them for a while. Unfortunately, opioid-induced constipation isn’t a side effect that improves over time.
It may be possible to prevent constipation from opioids by staying hydrated and exercising regularly. If this doesn’t work, you can consider using an over-the-counter (OTC) laxative. There are many types of laxatives that may be appropriate. Talk to your healthcare provider about which is best. A common approach is to try a stimulant laxative (like senna) and a stool softener (like docusate).
If OTC laxatives don’t work, you may need a prescription medication for constipation. Or your healthcare provider may recommend lowering your opioid dose or switching to another medication altogether. If constipation continues, let your provider know. Constipation that lasts for a long time can lead to complications like tears around the anus and stools that get stuck in your intestines.
2. Nausea
Nausea is another common side effect of opioids. In fact, nausea occurs in up to 40% of people taking opioids, and vomiting occurs in up to 25%.
Opioids cause nausea in various ways. They slow down the movement of food through your digestive tract and activate an area of the brain that causes nausea and vomiting.
If you’re experiencing nausea or vomiting while taking opioids, there are a few things you can try. For example, taking your medication with food may help prevent an upset stomach. Drinking water and avoiding spicy, fried, and fatty foods can also help. If these lifestyle changes don’t work, your healthcare provider may suggest taking an OTC nausea medication.
If you still have nausea or vomiting, you may need a prescription anti-nausea medication. Or you may need a lower opioid dose or need to switch to another medication entirely.
3. Drowsiness
Opioids are known to cause drowsiness. If you only take your opioid before bedtime, this side effect may not bother you. But if you take your opioid throughout the day and it’s affecting your daily activities, it can be more problematic.
Be careful doing activities that require you to be alert when taking an opioid — especially when first starting it or after a dose increase. This includes driving and operating heavy machinery.
If you’re experiencing significant drowsiness from opioids, talk to your healthcare provider. They may recommend lowering your dose to see if it helps. Or they may recommend taking a different type of pain medication.
4. Dizziness
Opioids are one type of medication that can cause dizziness due to their effects on the brain. Like drowsiness, dizziness makes it less safe to do activities that require alertness, like driving. If you’re starting an opioid or your dose was increased, hold off on driving until you see how it affects you.
If you feel dizzy, sitting or lying down can help until the dizziness passes. Drinking water or having a snack can also help. But talk to your healthcare provider if dizziness continues. They can help determine what’s causing it and whether you need to make any changes to your medications.
5. Itching
Opioids can cause itchiness. They seem to trigger itchiness by causing a type of immune system cell — called mast cells — to release histamine. Histamine is a chemical in the body that contributes to allergy symptoms, including itchy skin.
Using a gentle, hypoallergenic cleanser on your body and moisturizing cream may help. Avoiding fragrances and irritants can also help keep itching at bay. Oral OTC antihistamines like diphenhydramine (Benadryl) or loratadine (Claritin), and OTC creams like diphenhydramine/zinc acetate (Benadryl) and hydrocortisone 1% (or less), may also help.
If your itchiness is more severe, your healthcare provider may recommend a prescription medication (like a topical steroid).
Good to know: Itching is also a sign of an allergic reaction. Sometimes this can be severe. If you have signs of a severe allergic reaction, like hives, tightness in the throat, or trouble breathing, seek emergency care or call 911.
6. Tolerance
“Analgesic tolerance” is a term used to describe how an opioid dose loses its effectiveness over time. So after a while, you may need a higher opioid dose to get the same amount of pain relief you used to get with a lower dose. But higher opioid doses are more likely to lead to misuse and overdose.
You can help minimize tolerance to opioids by using the lowest effective dose for the shortest amount of time possible. If you need opioids long term, your healthcare provider may recommend adding another pain medication to your regimen. This may include acetaminophen (Tylenol) or ibuprofen (Motrin, Advil). In fact, some opioids come in a combination product with other pain relievers, like hydrocodone/acetaminophen and oxycodone/acetaminophen (Percocet).
If you think your opioid isn’t working as well as it used to, let your provider know. But don’t make any changes without talking to them first. Changing your opioid dose without their approval can be extremely dangerous.
7. Dependence and misuse
All opioids are controlled substances, which means they have a risk for dependence and misuse. Controlled substances are placed into categories, called “schedules,” by the DEA. These schedules range from 1 to 5. Schedule 1 controlled substances are illegal substances that are the most likely to cause dependence and misuse. Schedule 5 medications are considered the least risky of the controlled substances.
Most prescription opioids are Schedule 2 medications, except for tramadol, which is a Schedule 4 medication. Regardless of which opioid you take, use the lowest effective dose for the shortest amount of time possible. This will help minimize your risk of dependence or misuse.
Signs of dependence include tolerance to the opioid. Signs of misuse include mood changes like anxiety, restlessness, and anger. You may also notice new difficulties in your relationships. If you notice any of these changes, talk to your healthcare provider. They can evaluate you for an opioid use disorder if necessary.
8. Overdose
Opioids have a risk of overdose. An opioid overdose can slow your breathing to a point that’s dangerous, or even fatal. The risk is greatest when opioids are used in a way that’s not prescribed, such as taking more than what your healthcare provider recommends. But it can happen at prescribed doses, too. The risk is also higher when taking opioids with other substances that can affect your breathing, like benzodiazepines and sleep medications.
Besides trouble breathing, other signs of an opioid overdose include bluish skin, tiny pupils, and loss of consciousness. In severe cases, overdose can lead to death. That’s why it’s safest to only take your opioid as prescribed. And let your healthcare provider and pharmacist know what other medications you take. They’ll check to make sure you don’t take other medications that can make an overdose more likely.
Good to know: Naloxone (Narcan, Zimhi) is a life-saving medication that can reverse the effects of an opioid overdose. And it's available OTC as well as with a prescription from your provider. If you take an opioid, it’s a good idea for you and others in your household to keep naloxone on hand.
9. Withdrawal symptoms
If you’ve been taking opioids for a while and you stop them abruptly, you could experience withdrawal symptoms. Physical symptoms include sweating, diarrhea, and muscle aches. Mood-related symptoms include feeling restless, irritable, or depressed.
While opioid withdrawal isn’t usually life-threatening, it can be extremely uncomfortable. If you’re taking an opioid and you want to stop, talk to your healthcare provider and pharmacist. They can help you come up with a plan for slowly reducing your opioid dose.
When should I contact my healthcare provider about opioid side effects?
Contact your healthcare provider if you’re experiencing opioid side effects that are bothersome to you. While some side effects are mild and can be managed at home, others can be severe. If you experience trouble breathing, get immediate medical care by calling 911 or going to the nearest emergency room.
Don’t take more opioids than what your healthcare provider recommends. Doing so makes dependence, misuse, and overdose more likely.
The bottom line
Opioids are pain medications. Common opioid side effects include constipation, nausea, and drowsiness. Serious side effects include dependence, misuse, and overdose. You may also experience withdrawal symptoms if you stop taking opioids abruptly after taking them for a while.
Be sure to follow your healthcare provider’s instructions for how to safely take opioids. This helps minimize your risk of serious side effects. And it’s a good idea to have naloxone on hand if you’re taking opioids long term.
Why trust our experts?
If you or someone you know struggles with substance use, help is available. Call SAMHSA’s National Helpline at 1-800-662-4357 to learn about resources in your area.
References
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