Explaining the harmful effects of opioids

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This information leaflet tells you about the risks of taking opioids in the long term for chronic non-malignant pain (pain that is not caused by cancer). Opioids are useful for the short term management of acute pain (for example after surgery). However, when they are used in the long term they can cause harm.

Sensitivity and overdose

Sensitivity (where low doses can cause the same symptoms as overdose) or overdose may cause:

• your breathing and thinking to slow down
• your speech to be slurred
• your walking to be affected

You need to seek urgent medical care if you experience any of these symptoms. Overdose is not always caused by taking too much of your medication, it can happen for example if you are diagnosed with a new medical condition, begin a course of new medication or you have a short illness like flu.

Increased pain

Higher doses and long term use of opioids can make you become more sensitive to pain. This is due to changes in your nervous system. Increasing the dose further will not make your pain improve and increases your risk of becoming dependent on the medicine.

Hormone changes

Using opioid medication for more than six months can have an effect on sex hormones, which can cause impotence in men and loss of libido in both men and women. Long term opioid use has also been linked to infertility in men and women.

Drowsiness or change in thinking

You may not think as clearly when using opioid medication and this is likely to worsen with higher doses. Taking higher doses may make you feel ‘spaced out’ or ‘relaxed’ rather than reducing your pain. This might indicate that you are using the medication for the wrong reasons e.g. to relax or sleep, rather than reduce your pain.

Increased risk of physical dependence

This is a sign that your body has adapted to the medicines and you may experience withdrawal effects if you miss a dose or are late taking it. Early symptoms of withdrawal include: agitation, anxiety, muscle aches, increased tearing, insomnia, runny nose, sweating, and yawning. Late symptoms of withdrawal include: abdominal cramping; diarrhoea; dilated pupils; goose bumps; nausea and vomiting.

Decreased immune function

Long-term treatment reduces the activity of your immune system and can cause an increased risk of infection.

Poor muscle tone

The drowsiness and increased sensitivity to pain caused by taking opioids can make it difficult to exercise and stay active. This leads to poor muscle tone, which affects your posture, and stability and can make your pain feel worse.

Increased risk of falls and fractures

Long-term or high dose opioids increase your risk of falling and of developing osteoporosis, both of which can lead to bone fractures.

Depression and anxiety

There is an increased risk of depression and anxiety when you take opioids for long periods of time. This can make managing your pain even harder.

Dry mouth and constipation

• Lack of saliva can increase your risk of dental cavities and tooth loss
• Many patients need to take regular laxatives whilst taking opioids

What are the benefits of reducing opioids?

• You may experience less pain and be able to increase your activity, improve your mood and your ability to think more clearly
• You will feel less drowsy or ‘spaced out’ and be safer to drive
• You will have more energy and be able to gradually increase activity and exercise, which in turn can help reduce your pain levels
• Reduces your risk of side effects and harm to your general well-being
• Reduction must be made slowly to prevent unpleasant withdrawal effects

Never

• Stop or change your medication without discussing it with a healthcare professional first
• Share your medication with another person

Further information

Questions

• Do you still have pain despite your regular opioid medication?
• Does your medication cause side-effects that affect your daily activities (e.g. ability to drive)?