Abstral 400 microgram sublingual tablets – patient leaflet, side effects, dosage

1. What Abstral is and what it is used for

Abstral is a treatment for adults who must already regularly be taking strong pain-relieving medicine (opioids) for their persistent cancer pain, but require treatment for their breakthrough pain. If you are not sure, talk to your doctor.

Breakthrough pain is pain which occurs suddenly, even though you have taken or used your usual opioid pain-relieving medicine.

The active substance in Abstral sublingual tablets is fentanyl. Fentanyl belongs to a group of strong pain-relieving medicines called opioids.

2. What you need to know before you take Abstral

Do not take Abstral

• if you are allergic to fentanyl or any of the other ingredients of this medicine (listed in section 6)

• if you have severe breathing problems

  • if you are not regularly using a prescribed opioid medicine (e.g codeine, fentanyl, hydromorphone, morphine, oxycodone, pethidine), every day on a regular schedule, for at least a week, to control your persistent pain. If you have not been using these medicines you must not use Abstral because it may increase the risk that breathing could become dangerously slow and/or shallow, or even stop
  • if you suffer from short-term pain other than breakthrough pain
  • if you are being treated with medicines containing sodium oxybate

Warnings and precautions

Store this medicine in a safe and secure place, where other people cannot access it (see section 5. How to store Abstral for more information).

Talk to your doctor or pharmacist before taking Abstral if you have or have recently had any of the following, as your doctor will need to take account of these when prescribing your dose:

• a head injury, because Abstral may cover up the extent of the injury
• breathing problems or suffer from myasthenia gravis (a condition characterised by muscle weakness)
• if you have problems with your heart, especially a slow heart rate
• low blood pressure
• liver or kidney disease, as this may require your doctor to more carefully adjust your dose
• a brain tumour and/or raised intracranial pressure (an increase of pressure in the brain which causes severe headache, nausea/vomiting and blurred vision)
• mouth wounds or mucositis (swelling and redness of the inside of the mouth)
• if you take antidepressants or antipsychotics please refer to the section ‘Other medicines and Abstral’
• if you have ever developed adrenal insufficiency or lack of sex hormones (androgen deficiency) with opioid use

When taking Abstral, inform your doctor or dentist that you are taking this medicine, if:

• you are to have any surgery
• you experience pain or increased sensitivity to pain (hyperalgesia) which does not respond to a higher dosage of your medicine as prescribed by your doctor
• you experience a combination of the following symptoms: nausea, vomiting, anorexia, fatigue, weakness, dizziness, and low blood pressure. Together these symptoms may be a sign of a potentially life-threatening condition called adrenal insufficiency, a condition in which the adrenal glands do not produce enough hormones Long-term use and tolerance

This medicine contains fentanyl which is an opioid medicine. Repeated use of opioid painkillers can result in the drug being less effective (you become accustomed to it, known as drug tolerance). You may also become more sensitive to pain while using Abstral. This is known as hyperalgesia. Increasing the dose of Abstral may help to further reduce your pain for a while, but it may also be harmful. If you notice that your medicine becomes less effective, talk to your doctor. Your doctor will decide whether it is better for you to increase the dose or to gradually decrease your use of Abstral.

Dependence and addiction

This medicine contains fentanyl, which is an opioid. It can cause dependence and/or addiction.

Repeated use of Abstral can also lead to dependence, abuse and addiction which may result in life-threatening overdose. The risk of these side effects can increase with a higher dose and longer duration of use. Dependence or addiction can make you feel that you are no longer in control of how much medicine you need to use or how often you need to use it. You might feel that you need to carry on using your medicine, even when it doesn’t help to relieve your pain.

The risk of becoming dependent or addicted varies from person to person. You may have a greater risk of becoming dependent or addicted on Abstral if:

• you or anyone in your family have ever abused or been dependent on alcohol, prescription medicines or illegal drugs (“addiction”).

  • you are a smoker.
  • you have ever had problems with your mood (depression, anxiety or a personality disorder) or have been treated by a psychiatrist for other mental illness.

If you notice any of the following signs whilst using Abstral, it could be a sign that you have become dependent or addicted:

• you need to use the medicine for longer than advised by your doctor
• you need to use more than the recommended dose
• you are using the medicine for reasons other than prescribed, for instance, ‘to stay calm’ or ‘help you sleep’
• you have made repeated, unsuccessful attempts to quit or control the use of the medicine
• when you stop taking the medicine you feel unwell (e.g. nausea, vomiting, diarrhoea, anxiety, chills, tremor, and sweating), and you feel better once using the medicine again (‘withdrawal effects’) If you notice any of these signs, speak to your doctor to discuss the best treatment pathway for you, including when it is appropriate to stop and how to stop safely.

Sleep-related breathing disorders

Abstral can cause sleep-related breathing disorders such as sleep apnoea (breathing pauses during sleep) and sleep related hypoxemia (low oxygen level in the blood). The symptoms can include breathing pauses during sleep, night awakening due to shortness of breath, difficulties in maintaining sleep or excessive drowsiness during the day. If you or another person observe these symptoms, contact your doctor. A dose reduction may be considered by your doctor. Other medicines and Abstral

Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines (other than your regular opioid pain-relieving medicine).

Some medicines may increase or decrease the effects of Abstral. Therefore if you start, change the dose of, or stop therapy with the following medication tell your doctor as they may need to adjust your dose of Abstral:

• Certain types of antifungal medicines containing e.g. ketoconazole or itraconazole (used to treat fungal infections).
• Certain types of antibiotic medicines called macrolides, containing e.g. erythromycin (used to treat infections).
• Certain types of antiviral medicines called protease inhibitors, containing e.g. ritonavir (used to treat infections caused by viruses).
• Rifampin or rifabutin (medicines used to treat bacterial infections).
• Carbamazepine, phenytoin, or phenobarbital (medicines used to treat convulsions/fits).
• Herbal medicines containing St John’s wort (Hypericum perforatum).
• Medicines containing alcohol.
• Medicines called monoamine-oxidase (MAO) inhibitors, which are used for severe depression and Parkinson’s disease. Tell your doctor if you have taken this type of medicine within the last two weeks.
• Certain types of strong pain killers, called partial agonist/antagonists e.g. buprenorphine, nalbuphine and pentazocine (medicines for treatment of pain). You could experience symptoms of withdrawal syndrome (nausea, vomiting, diarrhoea, anxiety, chills, tremor, and sweating) while using these medicines. Abstral may add to the effect of medicines that make you feel sleepy (sedative medicines), including:
• other strong pain-relieving medicines (opioid-type medicines e.g. for pain and cough)
• some painkillers for nerve pain (gabapentin and pregabalin)
• general anaesthetics (used to make you sleep during operations)
• muscle relaxants
• sleeping tablets

• medicines used to treat

  ^○ depression

  ^○ allergies

  ^○ anxiety (such as benzodiazepines e.g. diazepam) and psychosis

• medicines containing clonidine (used to treat high blood pressure)

  Use of Abstral at the same time as medicines that make you feel sleepy (sedative medicines), such as benzodiazepines, increases the risk of drowsiness, difficulties in breathing (respiratory depression), coma and may be life-threatening. Because of this, use of Abstral together with sedative medicines should only be considered when other treatment options are not possible.

  However, if your doctor does prescribe Abstral together with sedative medicines, the dose and duration of treatment should be limited by your doctor.

  Please tell your doctor about all sedative medicines you are taking, and follow your doctor’s dose recommendation closely. It could be helpful to inform friends or relatives to be aware of the signs and symptoms stated above. Contact your doctor when experiencing such symptoms.

  The risk of certain other side effects increases if you are taking medicines such as certain antidepressants or antipsychotics. Abstral may interact with these medicines and you may experience mental status changes (e.g. agitation, hallucinations, coma), and other effects, such as body temperature above 38°C, increase in heart rate, unstable blood pressure, and exaggeration of reflexes, muscular rigidity, lack of coordination and/or gastrointestinal symptoms (e.g nausea, vomiting, diarrhoea). Your doctor will tell you whether Abstral is suitable for you.

  Abstral with food, drink and alcohol

  Abstral can make some people feel drowsy. Do not consume alcohol without consulting your doctor as it might make you feel more drowsy than usual.

  Do not drink grapefruit juice while you are prescribed Abstral treatment as it may increase the side effects of Abstral.

  Pregnancy and breast-feeding

  You must not use Abstral during pregnancy unless you have been specifically told to by your doctor. Fentanyl can get into breast milk and may cause side effects in the breast-fed infant. Do not use Abstral if you are breast-feeding. You should not start breast-feeding until at least 5 days after the last dose of Abstral. Ask your doctor or pharmacist for advice before taking any medicine when pregnant or breast-feeding.

  Driving and using machines

  Abstral may impair your mental and/or physical ability to perform potentially hazardous tasks such as driving or operating machinery.

  If you feel dizzy, sleepy or have blurred vision when you take Abstral, do not drive or use machinery.

  Driving in the UK

  This medicine can affect your ability to drive as it may make you sleepy or dizzy.

  Do not drive while taking this medicine until you know how this medicine affects you. It may be an offence to drive if your ability to drive safely is affected by taking this medicine. There is further information for patients who are intending to drive in the UK - go to www.gov.uk/drug-driving-law Talk to your doctor or pharmacist if you are not sure whether it is safe for you to drive while taking this medicine.

  Abstral contains sodium

  This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially ‘sodium-free’.

3. How to take Abstral

Before taking Abstral for the first time your doctor will explain how Abstral should be taken to effectively treat your breakthrough pain.

Before starting treatment and regularly during treatment, your doctor will also discuss with you what you may expect from using Abstral, when and how long you need to take it, when to contact your doctor, and when you need to stop it (see also section 2).

Always take this medicine exactly as your doctor has told you. Check with your doctor or pharmacist if you are not sure.

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Symptoms of overdose include:

• extreme drowsiness
• slow, shallow breathing
• coma

An overdose may also result in a brain disorder known as toxic leukoencephalopathy. If these occur, seek emergency medical help immediately.

If you think someone has taken Abstral by accident, seek emergency medical help immediately. If you stop taking Abstral

You should discontinue Abstral when you no longer have any breakthrough pain. You must however continue to take your usual opioid pain-relieving medicine to treat your persistent cancer pain as advised by your doctor. You may experience withdrawal symptoms similar to the possible side effects of Abstral when discontinuing Abstral. If you experience withdrawal symptoms or if you are concerned about your pain relief you should contact your doctor. Your doctor will evaluate if you need medicine to reduce or eliminate the withdrawal symptoms. There is a risk that you may become addicted to or dependent on these tablets (a need to keep taking the medicines). If you take these for a long time you can become used to the effects and you may need to take higher doses to control your pain.

You should not suddenly stop taking these tablets unless your doctor tells you to. If you want to stop taking you tablets, discuss this with your doctor first. They will tell you how to do this, usually by reducing the dose gradually so you do not experience unpleasant effects. If you suddenly stop taking these tablets you may get withdrawal symptoms such as

• agitation,
• anxiety,
• palpitations,
• shaking or
• sweating

If you have any further questions on the use of this medicine, ask your doctor or pharmacist.

4. Possible side effects

Like all medicines, this medicine can cause side-effects, although not everybody gets them. If you start to feel unusually or extremely sleepy or your breathing becomes slow or shallow, you or your carer should immediately contact your doctor or local hospital for emergency help (see also section 3 “If you take more Abstral than you should”).

Very common side effects (may affect more than 1 in 10 people) include:

• nausea

Common side effects (may affect up to 1 in 10 people) include:

• dizziness, headache, excessive sleepiness
• breathlessness/shortness of breath
• inflammation inside the mouth, vomiting, constipation, dry mouth
• sweating, weary/tired/lack of energy

Uncommon side effects (may affect up to 1 in 100 people) include:

• allergic reaction, trembling/shaking, disturbed or blurred vision, fast or slow heart beat, low blood pressure, memory loss

• depression, suspicious thoughts/ feeling afraid for no reason, feeling confused, feeling disorientated, feeling anxious/unhappy/restless, feeling unusually happy/healthy, mood swings

  • feeling full all the time, stomach-ache, indigestion
  • mouth ulcers, problems with tongue, pain in mouth or throat, tightness in throat, lip or gum ulcers
  • loss of appetite, loss of or change in sense of smell/taste
  • difficulty sleeping or disturbed sleep, disturbance in attention/easily distracted, lack of energy/weakness/loss of strength
  • abnormality in skin, rash, itchiness, night sweats, decreased sensitivity to touch, bruising easily
  • joint pain or stiffness, stiffness in muscles
  • drug withdrawal symptoms, (may manifest by the occurrence of the following side effects: nausea, vomiting, diarrhoea, anxiety, chills, tremor, and sweating), accidental overdose, in males an inability to get and/or keep an erection, feeling generally unwell

Side effects of frequency not known: (frequency cannot be estimated from the available data)

• swollen tongue, severe breathing problems, fall, flushing, feeling very warm, diarrhoea, convulsion (fits), swelling of arms or legs, seeing or hearing things that are not really there (hallucinations), fever, reduced level or loss of consciousness, itchy rash and delirium (symptoms may include a combination of agitation, restlessness, disorientation, confusion, fear, seeing or hearing things that are not really there, sleep disturbance, nightmares).
• drug tolerance, drug dependence (addiction), drug abuse (see section 2).

Prolonged treatment with fentanyl during pregnancy may cause withdrawal symptoms in the newborn which can be life-threatening (see section 2).

Reporting of side effects

If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.

By reporting side effects you can help provide more information on the safety of this medicine.

5. How to store Abstral

The pain-relieving medicine in Abstral is very strong and could be life-threatening if taken accidentally by a child. Abstral must be kept out of the sight and reach of children.

Store this medicine in a safe and secure place, where other people cannot access it. It can cause serious harm and be fatal to people who may take this medicine by accident, or intentionally when it has not been prescribed for them. It is recommended to keep Abstral in a locked storage space.

Do not use this medicine after the expiry date which is stated on the blister after EXP. The expiry date refers to the last day of that month.

Do not store above 25°C.

Store in the original blister in order to protect from moisture.

Any unused product should be taken, if possible, to your pharmacist to be disposed of safely. Do not throw away any medicines via wastewater or household waste. These measures will help protect the environment.

6. Contents of the pack and other information

What Abstral contains

The active substance is fentanyl. One sublingual tablet contains:

100 micrograms fentanyl (as citrate)

200 micrograms fentanyl (as citrate)

300 micrograms fentanyl (as citrate)

400 micrograms fentanyl (as citrate)

600 micrograms fentanyl (as citrate)

800 micrograms fentanyl (as citrate)

The other ingredients are mannitol (E421), silicified microcrystalline cellulose, croscarmellose sodium and magnesium stearate.

What Abstral looks like and contents of the pack

Abstral is a small white sublingual tablet to be inserted under the tongue. It comes in a range of different strengths and shapes. Your doctor will prescribe the strength (shape) and number of tablets suitable for you. The 100 microgram tablet is a white round tablet

The 200 microgram tablet is a white oval-shaped tablet

The 300 microgram tablet is a white triangle-shaped tablet

The 400 microgram tablet is a white diamond-shaped tablet

The 600 microgram tablet is a white “D”-shaped tablet

The 800 microgram tablet is a white capsule-shaped tablet

Abstral tablets are contained in blisters, available in cartons of 10 or 30 tablets.

Not all pack sizes may be marketed.

Marketing Authorisation Holder and Manufacturer:

Marketing Authorisation Holder:

Grünenthal Ltd

TOR Building

Saint Cloud Way

Maidenhead

Berkshire

SL6 8BN

United Kingdom

Manufacturer:

RECIPHARM LEGANÉS S.L.U.

Calle Severo Ochoa 13

Leganés, 28914 (Madrid)

Spain

This medicinal product is authorised in the Member States of the European Economic Area and in the United Kingdom (Northern Ireland) under the following names:

Abstral:

Cyprus, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Netherlands, Norway, Portugal, Spain, Sweden, United Kingdom (Northern Ireland).

Lunaldin:

Czech Republic, Estonia, Latvia, Lithuania, Slovak Republic, Romania

This leaflet was last revised in: 12 January 2026