Tolerance, dependence, and addiction
This medicine contains morphine which is an opioid medicine. Repeated use of opioids can result in the drug being less effective (you become accustomed to it, known as tolerance). Repeated use of Morphgesic SR Tablets 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 take or how often you need to take it.
The risk of becoming dependent or addicted varies from person to person. You may have a greater risk of becoming dependent on or addicted to Morphgesic SR Tablets 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 illnesses.
If you notice any of the following signs whilst taking Morphgesic SR Tablets, it could be a sign that you have become dependent or addicted:
- You need to take the medicine for longer than advised by your doctor
- You need to take 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, and you feel better once taking 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 (See section 3, If you stop taking Morphgesic SR Tablets).
Talk to your doctor or pharmacist before taking Morphgesic SR Tablets:
- if you have breathing problems such as impaired lung function;
- if you have any problems with your thyroid or adrenal glands;
- if you have impaired liver or kidney function;
- if you are a man with an enlarged prostate gland;
- if you have any problems urinating;
- if you have epilepsy or suffer from fits (seizures);
- if you are suffering with shock;
- if you are suffering from myasthenia gravis (a disease which affects the muscles);
- if you have bowel problems e.g. inflammatory or obstructive bowel disorder;
- if you have low blood pressure and a decreased volume of blood circulating (hypovolaemia);
- if you are or have ever been addicted to opioids, alcohol, prescription medicines, or illegal drugs
- if you have previously suffered from withdrawal symptoms such as agitation, anxiety, shaking or sweating, when you have stopped taking alcohol or drugs.
- if you have a severe heart problem after long-term lung disease (severe cor pulmonale);
- if you suffer with a disease of your bile duct;
- if you have pancreatitis (inflammation and swelling of the pancreas);
- if you have a rare form of tumour affecting part of the body known as the adrenal glands (phaeochromocytoma);
- if you are elderly.
- if you are taking any medicine from the group of medicines known as benzodiazepines.
Taking these medicines with Morphgesic SR Tablets may result in sedation, difficulties in breathing (respiratory depression), coma and may be fatal. Even if benzodiazepines are prescribed, your doctor may need to change the dose, the duration of treatment or monitor you regularly. - if you experience weakness, fatigue, lack of appetite, nausea, vomiting or low blood pressure. This may be a symptom of the adrenals producing too little of the hormone cortisol, and you may need to take hormone supplement.
- if you experience loss of libido, impotence, cessation of menstruation. This may be because of decreased sex hormone production.
- if you feel you need to take more of Morphine Sulfate Injection to get the same level of pain relief, this may mean you are becoming tolerant to the effects of this medicine or are becoming addicted to it. Speak to your prescriber who will discuss your treatment and may change your dose or switch you to an alternative pain reliever.
Acute generalized exanthematous pustulosis (AGEP) has been reported in association with Morphgesic SR Tablets treatment. Symptoms usually occur within the first 10 days of treatment. Tell your doctor if you have ever developed a severe skin rash or skin peeling, blistering and/or mouth sores after taking Morphgesic SR Tablets or other opioids. Stop using Morphgesic SR Tablets and seek medical attention immediately, if you notice any of the following symptoms: blistering, widespread scaly skin or pus-filled spots together with fever.
Sleep-related breathing disorders
Morphgesic SR Tablets 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 to maintain 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.
Contact your doctor if you experience severe upper abdominal pain possibly radiating to the back, nausea, vomiting or fever as this could be symptoms associated with inflammation of the pancreas (pancreatitis) and the biliary tract system.
Taking this medicine regularly, particularly for a long time, can lead to addiction. Your prescriber should have explained how long you will be taking it for and when it is appropriate to stop, how to do this safely.
Rarely, increasing the dose of this medicine can make you more sensitive to pain. If this happens, you need to speak to your prescriber about your treatment.
Addiction can cause withdrawal symptoms when you stop taking this medicine. Withdrawal symptoms can include restlessness, difficulty sleeping, irritability, agitation, anxiety, feeling your heartbeat (palpitations), increased blood pressure, feeling or being sick, diarrhoea, loss of appetite, shaking, shivering or sweating. Your prescriber will discuss with you how to gradually reduce your dose before stopping the medicine. It is important that you do not stop taking the medicine suddenly as you will be more likely to experience withdrawal symptoms.
Opioids should only be used by those they are prescribed for. Do not give your medicine to anyone else. Taking higher doses or more frequent doses of opioid, may increase the risk of addiction. Overuse and misuse can lead to overdose and/or death.
If any of these apply to you, or if you are not sure, tell your doctor before taking Morphgesic SR Tablets.
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines, including medicines obtained without a prescription.
Morphgesic SR Tablets must not be used together with a monoamine oxidase inhibitor, or if you have taken this type of medicine in the last two weeks (see section 'Do not take...'). Examples include tranylcypromide, phenelzine, isocarboxazid, moclobemide and linezolid.
This is especially important if you are taking any of the medicines mentioned below or medicines for:
- depression (e.g. amitriptyline, imipramine or dosulepin);
- psychoses (e.g. chlorpromazine, promazine);
- sedative or hypnotic purposes (e.g. zopiclone, zolpidem);
- gabapentin or pregabalin to treat epilepsy or neuropathic pain (pain due to nerve problems);
- other opioid analgesics such as buprenorphine, nalbuphine or pentazocine;
- anaesthesia (e.g. thiopental, isoflurane);
- palpitations (e.g. mexiletine or propranolol or esmolol);
- nausea and vomiting (e.g. metoclopramide, domperidone);
- ulcer healing (e.g. cimetidine, ranitidine);
- anti-histamine drugs;
- medicines to treat Parkinson's disease;
- rifampicin to treat tuberculosis;
- Some medicines used to treat blood clots (e.g. clopidogrel, prasugrel, ticagrelor) may have delayed and decreased effect when taken together with morphine.
- ritonavir to treat HIV;
- dexamfetamine to treat narcolepsy or attention-deficit hyperactivity disorder (ADHD);
- diuretic drugs to cause increase urine production;
- other analgesics (e.g. Buprenorphine, nalbuphine, pentazocine).
Morphine may increase the effects of medicines used to control high blood pressure, relax muscles or act as tranquilisers.
Concomitant use of Morphgesic SR Tablets and sedative medicines such as benzodiazepines or related drugs increases the risk of drowsiness, difficulties in breathing (respiratory depression), coma and may be life-threatening. Because of this, concomitant use should only be considered when other treatment options are not possible.
However, if your doctor does prescribe Morphgesic SR Tablets together with sedative medicines the dose and duration of concomitant 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.