Pentazocine/naloxone treats moderate-to-severe pain when non-opioid medications aren't controlling your pain well enough. It can start to work within 30 minutes, but it can cause serious side effects, such as slowed breathing, that can lead to death.
Moderate-to-severe pain that isn't relieved by non-opioid medications
Pentazocine/naloxone is a combination of two medications.
Pentazocine is an opioid partial agonist. It works on opioid receptors to change the way your brain and nervous system recognize and respond to pain. This lowers the amount of pain you feel.
Naloxone is an opioid antagonist. It blocks opioids from binding to the opioid receptors. This prevents the dangerous symptoms that can occur if people misuse the medication through self-injection.
Pentazocine/naloxone can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Personal or family history of substance or alcohol abuse | History of mental health conditions | Taking more of pentazocine/naloxone than prescribed or taking it for a long time
Taking pentazocine/naloxone can lead to abuse, misuse, or addiction, even if you take it at the recommended dose. This can cause serious problems, such as overdose and death. Because of this risk, the FDA has required pentazocine/naloxone and all opioids to be under a Risk Evaluation and Mitigation Strategy (REMS) program. This means your provider or pharmacist will talk to you about proper use, serious risks, and appropriate storage and disposal of this medication in order to keep you and your loved ones safe.
Risk factors: Age 65 years or older | History of severe chronic obstructive pulmonary disease (COPD) | History of severe weakness or muscle loss (debilitation) | Drinking alcohol | Taking medications that affect your mental state | Taking high doses of pentazocine/naloxone
Pentazocine/naloxone can slow your breathing down to the point where it's life-threatening. This can cause symptoms, such as shortness of breath, slow and shallow breathing, and bluish-colored lips, fingers, or toes. If this change in your breathing isn't recognized and treated right away, it can lead to death. Pentazocine/naloxone is especially dangerous for children, who can experience slowed breathing and death even from one accidental dose of the medication. If you notice these symptoms, call 911 and get medical help right away.
Though slowed breathing can happen at any time while you're taking pentazocine/naloxone, the risk is the highest when you first start the medication or when your dose is raised. Your provider will monitor you closely for slowed breathing for the first few days after you start taking pentazocine/naloxone or after they prescribe a higher dose.
Drinking alcohol and taking medications that affect your mental state, such as benzodiazepines, sedatives, some muscle relaxants, and some mental health medications, can slow your breathing even further, which can lead to unconsciousness, coma, and death.
Your provider might prescribe naloxone (Narcan), which is a medication that can temporarily reverse the effects of pentazocine/naloxone. It's important that you and your caregiver know when and how to administer naloxone (Narcan).
Risk factors: Long-term use during pregnancy
Taking pentazocine/naloxone for a long time during pregnancy can cause neonatal opioid withdrawal syndrome. This is a condition where your unborn baby becomes dependent on pentazocine/naloxone while in the womb because the medication is passed into their system through the placenta. Once your baby is born and they're no longer exposed to pentazocine/naloxone, they experience withdrawal symptoms, such as poor feeding or sucking, breathing problems, fever, high-pitched crying, or seizures. This can be life-threatening if it's not recognized and treated, and your baby will need special care after birth from experts in this area.
Pentazocine/naloxone can cause your body to produce less hormones. This is more likely to happen if you've been taking pentazocine/naloxone for more than one month. Let your provider know if you develop nausea, vomiting, loss of appetite, fatigue, weakness, dizziness, or low blood pressure, because these can be signs that your body isn't making enough hormones.
Risk factors: Age 65 years or older | History of low blood volume | Taking other medications that lower blood pressure | Taking certain medications that alter your mental state
Pentazocine/naloxone can cause extremely low blood pressure, including a drop in blood pressure when you stand from a sitting or lying down position. This can lead to dizziness and fainting. To avoid falling, get up slowly if you've been sitting or lying down. This drop in blood pressure is more likely to happen when you first start pentazocine/naloxone or when your dose is raised. If dizziness or lightheadedness doesn't go away, talk to your healthcare provider.
Pentazocine/naloxone can cause hallucinations, confusion, or it can make you feel lost. This usually goes away within a few hours. Let your provider know if you experience any of these symptoms because they'll need to monitor you very closely.
Risk factors: History of seizures
If you have a condition that causes seizures, pentazocine/naloxone can make you have seizures more often. It can also raise your risk of seizures in certain situations even if you haven't had a seizure in the past. Before you start taking pentazocine/naloxone, let your healthcare provider know if you have a history of seizures.
Risk factors: Taking medications that can raise serotonin levels in your body
Taking opioids like pentazocine/naloxone with medications that can raise the serotonin levels in your body can cause a rare, but life-threatening condition called serotonin syndrome. This is because of very high levels of serotonin in your blood, which can cause a racing heart, unstable blood pressure, high fever, sudden changes in thought, mood, and movement, and hallucinations. If you experience any of these symptoms, seek medical help right away.
Examples of medications that can raise your serotonin levels include sertraline (Zoloft), fluoxetine (Prozac), bupropion (Wellbutrin), duloxetine (Cymbalta), and amitriptyline. Let your provider know if you are taking or planning to take any of these medications before starting pentazocine/naloxone.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Rare
Black, tarry stools
chills
difficult or troubled breathing
general feeling of tiredness or weakness
hoarseness
irregular, fast or slow, or shallow breathing
lower back or side pain
painful or difficult urination
pale or blue lips, fingernails, or skin
shakiness in the legs, arms, hands, or feet
sores, ulcers, or white spots on the lips or in the mouth
swollen glands
trembling or shaking of the hands or feet
unusual bleeding or bruising
unusual tiredness or weakness
Incidence not known
Agitation
blistering, peeling, or loosening of the skin
blurred vision
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
confusion
constricted, pinpoint, or small pupils (black part of the eye)
darkening of the skin
decrease in the frequency of urination
difficulty in passing urine (dribbling)
difficulty with swallowing
dizziness
dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
excitement
fainting
false or unusual sense of well-being
fast, slow, pounding, or irregular heartbeat or pulse
feeling of warmth
headache
hives or welts, itching, skin rash
joint or muscle pain
loss of bladder control
loss of consciousness
nervousness
overactive reflexes
poor coordination
pounding in the ears
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
rapid breathing
red skin lesions, often with a purple center
red, irritated eyes
redness of the face, neck, arms, and occasionally, upper chest
restlessness
sweating
swelling of the face, arms, or lower legs
tightness in the chest
total body jerking
upper abdominal or stomach pain
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
choking
cold and clammy skin
constricted, pinpoint, or small pupils (black part of the eye)
coughing that sometimes produces a pink frothy sputum
decreased awareness or responsiveness
difficult, fast, or noisy breathing
extremely shallow or slow breathing
increased sweating
loss of consciousness
no muscle tone or movement
pale skin
seeing, hearing, or feeling things that are not there
severe sleepiness or unusual drowsiness
seizures (convulsions)
slow heartbeat
swelling in the legs and ankles
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Rare
Stomach distress
Incidence not known
Continuing ringing or buzzing or other unexplained noise in the ears
cracked, dry, or scaly skin
difficulty in focusing the eyes
disturbed dreams
drowsiness
hearing loss
irritability
lightheadedness
loss of appetite
mood or mental changes
relaxed and calm feeling
trouble with sleeping
vomiting
weakness
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Relieves pain quickly in 15 to 30 minutes
Contains naloxone, which lowers your risk of having symptoms if misused (when it's given through an injection)
Available in a lower-cost generic form
Has a risk of addiction and overdose even if you take the medication at the recommended dose
Can cause life-threatening, slowed breathing that can lead to death
Generally not recommended for people 65 years and older
Pentazocine/naloxone can cause sleepiness, dizziness, or lightheadedness. Don't drive or do anything that requires you to focus until you know how this medication affects you.
Don't stop taking pentazocine/naloxone or lower your dose without talking to your provider. Stopping this medication suddenly can cause withdrawal symptoms, such as uncontrolled pain, suicidal thoughts, sweating, restlessness, nausea, vomiting, diarrhea, muscle pain, watery eyes, and wide pupils.
Don't drink alcohol or take any medications that contain alcohol while you're taking pentazocine/naloxone. Drinking alcohol with this medication can lead to an overdose and even death.
There are serious risks, such as death, that can occur if pentazocine/naloxone is accidentally taken by someone it's not prescribed for, if it's used for a reason other than what it's prescribed for (misuse), or if it's abused. Store this medication out of reach of children and in a location that can't be easily accessed by visitors to your home. If you no longer need pentazocine/naloxone or if it's expired, throw the medication away through a drug take-back program or by flushing it down the toilet.
Your provider might prescribe naloxone (Narcan), which is a medication that can treat pentazocine/naloxone overdose. It's important that you and your caregiver know when and how to administer naloxone (Narcan) in case an accidental overdose happens.
Constipation is a common side effect of pentazocine/naloxone. Drink plenty of water and eat fiber-rich foods, such as apples or broccoli.
Your provider will work with you to prescribe the right dose of pentazocine/naloxone for your individual needs. It's recommended to use the lowest dose possible for the shortest duration of time to manage your pain.
In general, the typical starting dose is 1 tablet by mouth every 3 to 4 hours. Each tablet contains 50 mg of pentazocine and 0.5 mg of naloxone.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Severely slowed breathing
Severe asthma
Blockage or narrowing in your stomach or intestines
Moderate-to-severe pain that isn't relieved by non-opioid medications
Pain that isn't relieved by non-opioid pain medications alone
Pain that isn't relieved by non-opioid pain medications alone
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