Package Leaflet: Information for the User
Duoxona 40 mg/20 mg prolonged-release tablets EFG
Oxycodone hydrochloride / Naloxone hydrochloride
Read all of this leaflet carefully before you start taking this medicine because it contains important information for you.
Contents of the pack
Duoxona is a prolonged-release tablet, which means that the active substances are released over a longer period of time. Its effect lasts 12 hours.
These tablets are for use in adults only.
Pain relief
You have been prescribed Duoxona for the treatment of severe pain, which can only be adequately managed with opioid analgesics. Naloxone hydrochloride is added to counteract constipation.
How these tablets work for pain relief
These tablets contain oxycodone hydrochloride and naloxone hydrochloride as active substances. Oxycodone hydrochloride is responsible for the analgesic effect of Duoxona; it is a potent analgesic from the opioid group.
The second active substance of Duoxona, naloxone hydrochloride, has the function of counteracting constipation. Gastrointestinal dysfunction (e.g. constipation) is a common side effect of treatment with opioid analgesics.
Do not take Duoxona
Warnings and precautions
Tell your doctor or pharmacist before you start taking this medicine:
Contact your doctor if you have severe abdominal pain that may radiate to the back, nausea, vomiting, or fever, as these may be symptoms associated with pancreatitis and biliary tract disease.
Tell your doctor if you have had any of these diseases in the past. Also, inform your doctor if you develop any of these diseases during treatment with these tablets.
The most serious consequence of opioid overdose is respiratory depression (slow and shallow breathing). This can also lead to a decrease in oxygen concentration in the blood, which can cause fainting, etc.
Tell your doctor if you have cancer associated with peritoneal metastasis or initial intestinal obstruction in advanced stages of digestive and pelvic cancers.
Tolerance, dependence, and addiction
This medicine contains oxycodone, which is an opioid, and can cause dependence and/or addiction. |
This medicine contains oxycodone, which is an opioid medicine. Repeated use of opioid analgesics may lead to tolerance (you may need to take more to achieve the same level of pain relief) and physical dependence. The risk of these side effects may increase with higher doses and longer treatment duration.
Dependence or addiction can make you feel that you no longer have control over the amount of medicine you need to take or how often you need to take it. You may feel that you need to keep taking the medicine even when it no longer helps with your pain.
The risk of becoming dependent or addicted varies from person to person. You may have a higherrisk of becoming dependent or addicted to Duoxona:
If you notice any of the following signs while taking Duoxona, it could be a sign thatyou have become dependent or addicted.
If you notice any of these signs, talk to your doctor to discuss the best treatment for you, including when it is appropriate to stop taking it and how to do so safely (see section 3, If you stop taking Duoxona).
Breathing difficulties related to sleep
Duoxona may cause breathing difficulties related to sleep, such as sleep apnea (pauses in breathing during sleep) and sleep-related hypoxemia (low oxygen levels in the blood). Symptoms may include pauses in breathing during sleep, nighttime awakenings due to difficulty breathing, difficulty staying asleep, or excessive daytime sleepiness. If you or someone else observes these symptoms, consult your doctor. Your doctor may consider reducing the dose.
Children and adolescents under 18 years
The safety and benefits of oxycodone/naloxone in children and adolescents under 18 years have not been established.
How to take Duoxona correctly
Diarrhea
If you experience severe diarrhea at the start of treatment, it may be due to the effect of naloxone. It may be a sign that bowel function is returning to normal. This diarrhea may occur in the first 3 to 5 days of treatment. If it persists beyond this period or if you are concerned, contact your doctor.
Switching to Duoxona
If you have been receiving another opioid, you may experience withdrawal symptoms shortly after starting treatment with oxycodone/naloxone, e.g. restlessness, sweating, and muscle pain. If you experience any of these symptoms, you may need special monitoring by your doctor. This medicine is not suitable for the treatment of withdrawal syndrome.
Surgery
If you need to undergo surgery, tell the doctors that you are taking oxycodone/naloxone.
Long-term treatment
If administered for a long time, you may develop tolerance to oxycodone/naloxone. This means you may need higher doses to achieve pain relief. Long-term administration of oxycodone/naloxone may lead to physical dependence. If treatment is stopped suddenly, withdrawal symptoms (restlessness, sweating, and muscle pain) may occur. If treatment is no longer necessary, it is recommended to gradually reduce the daily dose with the help of your doctor.
Psychological dependence
The abuse profile of oxycodone hydrochloride alone is similar to that of other potent opioids (strong painkillers). There is a possibility of psychological dependence. Medicines containing oxycodone hydrochloride should be used with special caution in patients with a history of alcohol, drug, or medicine abuse.
Incorrect use of Duoxona
These tablets are not suitable for the treatment of withdrawal syndrome.
The tablet can be divided, but it must not be broken, chewed, or crushed.
To avoid damaging the prolonged-release properties of the tablet, it must not be crushed or chewed, as this can lead to the absorption of a potentially lethal dose of oxycodone hydrochloride (see “If you take more Duoxona than you should”).
Abuse
Oxycodone/naloxone should never be used if you are addicted to substances such as heroin, morphine, or methadone, as it may cause severe withdrawal symptoms, since it contains naloxone. It may worsen pre-existing withdrawal symptoms.
Duoxona should never be dissolved for injection (e.g. into a blood vessel). The reason is that it contains talc, which can cause local tissue destruction (necrosis) and changes in lung tissue (pulmonary granuloma). This abuse can also have other serious consequences and even be fatal.
Athletes should be aware that the use of this medicine may result in positive doping tests. The use of oxycodone/naloxone as a doping agent can endanger health.
Taking Duoxona with other medicines
Tell your doctor or pharmacist if you are taking, have recently taken, or might take any other medicines.
Concomitant use of oxycodone/naloxone and sedative medicines such as benzodiazepines or related medicines increases the risk of drowsiness, breathing difficulties (respiratory depression), coma, and can be life-threatening. Therefore, concomitant use should only be considered when other treatment options are not possible.
However, if your doctor prescribes oxycodone/naloxone together with sedative medicines, your doctor should limit the dose and duration of concomitant treatment.
Tell your doctor about all sedative medicines you are taking and strictly follow your doctor's dosage recommendations. It may be useful to inform friends or family members to be aware of the signs and symptoms mentioned above. Contact your doctor when you experience such symptoms.
Concomitant use of these tablets and other medicines may alter the effect of oxycodone/naloxone and the other medicines. Tell your doctor if you are taking:
No interactions are expected between oxycodone/naloxone and paracetamol, acetylsalicylic acid, or naltrexone.
Taking Duoxona with food, drinks, and alcohol
Drinking alcohol while taking this medicine may make you feel more drowsy or increase the risk of serious side effects such as shallow breathing with the risk of stopping breathing, and loss of consciousness. It is recommended not to drink alcohol while taking oxycodone/naloxone.
You should avoid drinking grapefruit juice while taking these tablets.
Pregnancy and breastfeeding
If you are pregnant or breastfeeding, think you may be pregnant, or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.
Pregnancy
During pregnancy, these tablets should be avoided whenever possible. If used during prolonged periods of pregnancy, oxycodone hydrochloride may cause withdrawal symptoms in the newborn. If oxycodone hydrochloride is administered during labor, the newborn may experience respiratory depression (slow and shallow breathing).
Breastfeeding
Breastfeeding should be discontinued during treatment with these tablets. Oxycodone hydrochloride passes into breast milk. It is not known whether oxycodone hydrochloride also passes into breast milk. Therefore, the risk to the breastfed child cannot be excluded, especially if the mother receives multiple doses of oxycodone/naloxone.
Driving and using machines
Duoxona may affect your ability to drive and use machines. This is especially true at the start of treatment with oxycodone/naloxone, after a dose increase, or after switching from another medicine. However, these side effects disappear once the dose of this medicine is established.
Oxycodone/naloxone has been associated with drowsiness and sudden sleep episodes. If you experience these side effects, do not drive or use machinery. If this happens, inform your doctor.
Ask your doctor if you can drive or use machines during treatment with Duoxona.
Follow the administration instructions for this medication exactly as indicated by your doctor. In case of doubt, consult your doctor or pharmacist again.
Duoxona is a prolonged-release tablet, which means that the active ingredients are released over a prolonged period of time. Its action lasts 12 hours.
The tablet can be divided, but it should not be broken, chewed, or crushed.
To avoid damaging the prolonged-release properties of the tablet, it should not be crushed or chewed, as this may cause the absorption of a potentially lethal dose of oxycodone hydrochloride (see "If you take more Duoxona than you should").
Before starting treatment and periodically during treatment, your doctor will discuss with you what you can expect from using Duoxona, when and for how long you should take it, when to contact your doctor, and when to stop taking it (see also "If you stop taking Duoxona").
Unless your doctor tells you otherwise, the usual dose is:
For pain treatment
Adults
The usual initial dose is 10 mg of oxycodone hydrochloride / 5 mg of naloxone hydrochloride in prolonged-release tablets every 12 hours.
Your doctor will decide the dose you should take per day and how to divide the total daily dose between the morning and evening doses. Your doctor will also decide if it is necessary to adjust the dose during treatment. Your dose will be adapted to your degree of pain and individual sensitivity. You should receive the minimum dose necessary to relieve pain. If you have already received treatment with opioids, the initial dose of Duoxona may be higher.
The maximum daily dose is 160 mg of oxycodone hydrochloride and 80 mg of naloxone hydrochloride. If you need a higher dose, your doctor may prescribe more oxycodone hydrochloride without naloxone hydrochloride. However, the maximum daily dose of oxycodone hydrochloride should not exceed 400 mg. The beneficial effect of naloxone hydrochloride on intestinal activity may be affected if the dose of oxycodone hydrochloride is increased without increasing the dose of naloxone hydrochloride.
If you replace these tablets with another opioid analgesic, it is likely that your intestinal function will worsen. If you experience pain between two doses of Duoxona, you may need a fast-acting analgesic. Duoxona is not suitable for treatment in this case. Discuss this with your doctor.
If you feel that the effect of these tablets is too strong or too weak, consult your doctor or pharmacist.
For pain treatment
Elderly patients
In general, it is not necessary to adjust the dose in elderly patients with normal kidney and/or liver function.
Liver or kidney disorder
If you have kidney disorder of any degree or mild liver disorder, your doctor will prescribe these tablets with special caution. If you have moderate or severe liver disorder, you should not take these tablets (see also section 2 "Do not take Duoxona" and "Warnings and precautions").
Children and adolescents under 18 years
Duoxona has not been studied in children and adolescents under 18 years. Its safety and efficacy have not been demonstrated in these patients. For this reason, the use of Duoxona is not recommended in children and adolescents under 18 years.
Method of administration
Oral route.
Take Duoxona every 12 hours, following a fixed schedule (e.g., at 8 am and 8 pm).
Swallow these tablets with enough liquid (half a glass of water). Do not break, crush, or chew the tablets. You can take the tablets with or without food.
Duration of use
In general, you should not take these tablets for longer than necessary. If you receive these tablets for a long time, your doctor should regularly check that you still need them.
If you take more Duoxona than you should
If you have taken more tablets than prescribed, you should inform your doctor immediately. Consult your doctor or pharmacist immediately or call the Toxicology Information Service, phone 91 562 04 20, indicating the medication and the amount used. It is recommended to take the package and the package leaflet of the medication to the healthcare professional.
An overdose can cause:
In severe cases, loss of consciousness (coma), fluid accumulation in the lungs, and circulatory collapse may occur, which can be fatal in some cases.
You should avoid situations that require a high level of alertness, such as driving.
If you forget to take Duoxona
If you forget to take Duoxona or if you take a lower dose than prescribed, you may not notice the analgesic effect.
If you forget to take a dose, follow these instructions:
Do not take a double dose to make up for forgotten doses.
If you stop taking Duoxona
Do not stop treatment without consulting your doctor. If you no longer need to continue treatment, you should gradually reduce the daily dose, after discussing it with your doctor. This will help you avoid withdrawal symptoms, such as restlessness, sweating, and muscle pain.
If you have any other questions about the use of this medication, ask your doctor or pharmacist.
Like all medications, this medication can cause side effects, although not everyone experiences them.
Important side effects to look for, and what to do if you experience them:
If you already have any of the following important side effects, consult your doctor immediately.
Slow and shallow breathing (respiratory depression) is the main danger of opioid overdose. It occurs mainly in elderly and debilitated patients. Opioids can also cause a significant decrease in blood pressure in susceptible patients.
Side effects are subdivided into two sections: pain treatment and treatment with only the active ingredient oxycodone hydrochloride.
The following side effects have been observed in patients receiving treatment for pain
Frequent (may affect up to 1 in 10 patients)
Uncommon (may affect up to 1 in 100 patients)
Rare (may affect up to 1 in 1,000 patients)
Frequency not known (cannot be estimated from available data)
It is known that the active ingredient oxycodone hydrochloride, if not combined with naloxone hydrochloride, has the following side effects, different from those listed:
Oxycodone may cause respiratory problems (respiratory depression), decreased pupil size, bronchial and smooth muscle spasms, and depression of the cough reflex.
Frequent (may affect up to 1 in 10 patients)
Uncommon (may affect up to 1 in 100 patients)
Rare (may affect up to 1 in 1,000 patients)
Frequency not known (cannot be estimated from available data)
Reporting side effects
If you experience any side effects, consult your doctor or pharmacist, even if they are possible side effects not listed in this leaflet. You can also report them directly through the Spanish Medicines Monitoring System: www.notificaRAM.es. By reporting side effects, you can help provide more information on the safety of this medication.
Keep this medication out of sight and reach of children.
Store this medication in a safe and closed place, where others cannot access it. It can cause serious harm and be fatal to people who have not been prescribed it.
Do not use this medication after the expiration date shown on the box or blister pack, after "EXP". The expiration date is the last day of the month indicated.
Blister pack:
Do not store above 25°C.
Medications should not be disposed of through wastewater or household waste. Deposit the packaging and medications you no longer need at the SIGRE collection point in the pharmacy. If in doubt, ask your pharmacist how to dispose of the packaging and medications you no longer need. This will help protect the environment.
Duoxona composition
The active ingredients are oxycodone hydrochloride and naloxone hydrochloride.
Each prolonged-release tablet contains 40 mg of oxycodone hydrochloride (equivalent to 36 mg of oxycodone) and 20 mg of naloxone hydrochloride (as 21.8 mg of naloxone hydrochloride dihydrate, equivalent to 18 mg of naloxone).
The other ingredients are:
Appearance of Duoxona and package contents
Duoxona 40 mg/20 mg are prolonged-release tablets, pink, oblong, and biconvex with break lines on both sides, with a length of 14.2 mm, a width of 6.7 mm, and a height of 5.0 mm. The tablet can be divided into equal doses.
These tablets are available in child-resistant blister packs of 10, 14, 20, 28, 30, 50, 56, 60, 90, 98, and 100 tablets or screw-cap bottles with child-resistant caps containing 50, 100, or 250 tablets.
Not all pack sizes may be marketed.
Marketing authorization holder and manufacturer
Marketing authorization holder
NEURAXPHARM SPAIN, S.L.U.
Avda. Barcelona, 69
08970 Sant Joan Despí
Barcelona - Spain
Manufacturer
Develco Pharma GmbH
Grienmatt 42
79650 Schopfheim
Germany
or
Neuraxpharm Arzneimittel GmbH
Elisabeth-Selbert-Str. 23
40764 Langenfeld
Germany
or
Saneca Pharmaceuticals A.S.
Nitrianska 100, Slovakia-920 27 Hlohovec
This medication is authorized in the Member States of the European Economic Area under the following names:
Czech Republic | Duoxona |
Germany | Oxycodon-HCl/Naloxon-HCl neuraxpharm 5 mg/2.5 mg; 10 mg/5 mg; 20 mg/10 mg; 30 mg/15 mg; 40 mg/20 mg Retardtabletten |
Italy | Duoxona |
Finland | Duoxona 5 mg/2.5 mg depottabletit; Duoxona 10 mg/5 mg depottabletit; Duoxona 30 mg/15 mg depottabletit; Duoxona 40 mg/20 mg depottabletit |
Slovakia | Duoxona 5 mg/2.5 mg; 10 mg/5 mg; 20 mg/10 mg; 30 mg/15 mg; 40 mg/20 mg tablety s predlženým uvolnovaním |
Spain | Duoxona 5 mg/2.5 mg comprimidos de liberación prolongada EFG Duoxona 10 mg/5 mg comprimidos de liberación prolongada EFG Duoxona 20 mg/10 mg comprimidos de liberación prolongada EFG Duoxona 30 mg/15 mg comprimidos de liberación prolongada EFG Duoxona 40 mg/20 mg comprimidos de liberación prolongada EFG |
Iceland | Duoxona 5 + 2.5 mg forðatafla; Duoxona 10 + 5 mg forðatafla; Duoxona 20 + 10 mg forðatafla; Duoxona 30 + 15 mg forðatafla; Duoxona 40 + 20 mg forðatafla |
Sweden | Duoxona 5 mg/2.5 mg Depottablett; Duoxona 10 mg/5 mg Depottablett; Duoxona 20 mg/10 mg Depottablett; Duoxona 30 mg/15 mg Depottablett; Duoxona 40 mg/20 mg Depottablett |
Norway | Duoxona 5mg/2.5mg depotablett; Duoxona 10mg/5mg depotablett; Duoxona 20mg/10mg depotablett; Duoxona 30mg/15mg depotablett; Duoxona 40mg/20mg depotablett |
Date of last revision of this leaflet: April 2025
"Detailed and updated information on this medication is available on the website of the Spanish Agency for Medicines and Health Products (AEMPS) http://www.aemps.gob.es/
The average price of DUOXONA 40 MG/20 MG PROLONGED-RELEASE TABLETS in October, 2025 is around 101.53 EUR. Prices may vary depending on the region, pharmacy, and whether a prescription is required. Always check with a local pharmacy or online source for the most accurate information.
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