Understanding medicines and using them better

This chapter aims to help you understand:

•   What types of medicines are used to manage chronic pain

•   How are medicines used

•   What the problems are with medicines

•   How to make better use of medicines

•   How to reduce or stop your use of medicines

If you are taking medicines for pain, it may be useful to ask yourself the following questions:

•   How long have you used your pain-relief medicines?

•   Have they helped reduce your pain?

•   Have you any side-effects, problems or concerns about your medicines?

•   Do you ever try to cope without them?

This chapter gives you guidance on using your medicines in helpful ways and making decisions about changes with your doctor at any stage. The chapter mentions the most common medicines used to reduce pain and does not include all the possible ones that manage pain.

What types of medicines are used to manage chronic pain?

There are four main types of medicines that are used to manage pain: analgesics (including opioids), anti-inflammatories, anti-depressants and anti-convulsants.

ANALGESICS

Analgesics, like paracetamol, codeine, dihydrocodeine, buprenorphine, tramadol, morphine, fentanyl, oxycodone are often called ‘painkillers’.

Opioids, like codeine, dihydrocodeine and morphine, are chemical or drug forms of pain relief susbstances found in opium poppy seeds. There are several newer opioid drugs, like tramadol, fentanyl and buprenorphine.

The body also makes its own opioid-like substances, called endorphins, which can help reduce the pain experience. Exercise and physical activity or relaxation can increase endorphins, and raised endorphins create a feeling of happiness or euphoria, sometimes known as a ‘runner’s high’. All these opioid drugs mimic the action of the endorphins’ pain relief effects. They attach to the opioid receptors in the brain and spinal cord to reduce pain signals in the pain systems.

The word ‘painkiller’ suggests that analgesics relieve pain completely. However, most people with chronic pain find that these drugs can be used to help reduce or control the pain, but do not relieve it totally.

Common side-effects of analgesics include: constipation, feeling sick, itching, dizziness, loss of concentration, forgetfulness, dry mouth, mood changes, such as depression, and sleep problems, sometimes including dreams or nightmares.

ANTI-INFLAMMATORIES

Anti-inflammatories reduce inflammation and pain, e.g.:

•   In acute injuries, like a twisted ankle

•   Around joints, for example in osteoarthritis or rheumatoid arthritis

•   In sore throats

•   After the removal of a tooth

Inflammation shows as swelling or redness of the affected area and this causes pain. Inflammation is caused by a release of many helpful chemicals in the injured or infected area. These chemicals send pain messages through the nerve endings in the area to the brain’s pain centres. The same chemicals help the body to limit any further damage from the injury and start the healing process. They also work with the body’s immune system to control infection.

Some frequently used anti-inflammatory drugs include: ibuprofen (Brufen), indomethacin (Indocid) and diclofenac (Voltarol). These drugs are known as non-steroidal anti-inflammatory drugs.

Common side-effects of anti-inflammatory drugs include: skin rashes, indigestion, and bleeding from the gut, stomach or bowel. They can sometimes worsen asthma symptoms.

ANTI-DEPRESSANTS

Anti-depressants or tricyclic anti-depressants, such as amitriptyline, imipramine or dothiepin, are usually used in treating depression. Research has shown them to be also very useful in helping to reduce chronic pain and sleep problems (both helping getting off to sleep and reducing waking from sleep due to pain). For example, with amitriptyline, the dose used to manage chronic pain is usually quite small, between 5 mg and 25 mg. In depression, the dose used is up to ten times larger, between 100 and 200 mg.

Common side-effects of these anti-depressants include: constipation, dry mouth, drowsiness, abdominal pain due to colic or constipation, dizziness, blurred vision and poor concentration.

ANTI-CONVULSANTS

Anti-convulsants, such as carbamazepine and gabapentin, are used for pain. They are also used to treat epilepsy. They can reduce pain coming from nerve fibres, called neuropathic pain. Research shows it can help reduce pain in diabetes neuropathy and is sometimes helpful in trigeminal neuralgia or after shingles (post herpetic neuralgia).

Common side-effects of anti-convulsants include: drowsiness, rashes, nausea and vomiting, dizziness, and unsteadiness or balance difficulties.

Note: Current medical opinion states that tranquillizers, or muscle and mind relaxants, such as diazepam (Valium) and lorazepam (Ativan), which are sometimes used to control convulsions, have no use in acute back pain management. This would suggest that they have no use in treating any kind of chronic pain. Dependence can be a real problem with these drugs. If they have been used for months or years, careful support from a healthcare practitioner is essential in order to help people reduce their dose.