by Gerard Hall
There are a number of causes of back pain and the choice of a prescribed drug obviously depends on the diagnosis. Simple muscular or postural back pain may respond to paracetamol or a mild anti-inflammatory drug, but more severe pain may require codeine preparations or other drugs that affect pain pathways. Let’s take a look at the most frequently used medications.
Paracetamol is the most common painkiller in the UK. It is the drug of choice for simple pain because it is generally very safe and is well tolerated by most patients. The maximum dose is two tablets every six hours and must not be exceeded. It can, in rare circumstances, cause kidney damage, but it does not usually cause stomach problems or drowsiness and it can be taken with most other medication. However, care must be taken not to combine it with other products that contain paracetamol.
If paracetamol proves to be inadequate at treating the pain, then compound analgesics are the next step up in strength. Paracetamol is usually combined with either codeine (Cocodamol) or a codeine derivative (codydramol, tramadol), but there are a number of different proprietary variations. Although codeine is a very effective drug, common side effects include constipation, light-headedness and drowsiness, and there are also concerns of codeine addiction with long-term or over usage.
Tramadol is an analgesic with codeine-like action and is an opiod receptor agonist, but it is less likely to cause constipation, drowsiness or dependency. A small number of patients withdraw treatment due to unpleasant side effects, which include disorientation and confusion.
NSAIDs (non-steroidal anti-inflammatory drugs) are available in low doses over the counter and include preparations of Ibuprofen and Diclofenac. Higher doses of these drugs are prescribable, as are a number of other NSAIDs such as naproxen and indomethacin. These drugs have analgesic properties as well as being anti inflammatory and can be helpful for treating those with simple back pain as well as those who have inflammatory causes of back pain.
They are generally given as courses lasting a few days or weeks, but some patients may take them in the long term. They are generally well tolerated, but there are a number of side effects associated with NSAIDs, including indigestion, abdominal pain and diarrhoea. They can also affect the kidneys and blood pressure, so caution should be exercised in patients who have a history of kidney problems, hypertension or heart disease.
Over the last decade, a new group of anti-inflammatory drugs has emerged, commonly referred to as COX-2 inhibitors. These drugs have fewer side effects on the stomach and bowel, but they may still have a potential effect on the cardiovascular system. Etoricoxib and Meloxicam are the most common of these drugs in the UK.
Pregabalin and Gabapentin
Pregabalin and Gabapentin are neuromodulators that were originally developed for the treatment of epilepsy, but they also have an effect on pain pathways. They are especially helpful for patients with long-term pain and those with neural pain, such as nerve compression causing arm pain. They may cause drowsiness and some cognitive dysfunction and they are also expensive.
Amitryptilline and Nortryptilline
Amitryptilline and Nortryptilline are tricyclics dugs used for depression at full doses of 75-150mg daily. In much lower doses, just 10-25mg a day, they are effective in improving sleep patterns and for the treatment of pain – particularly neural pain. They are taken an hour before bedtime and the most common side effects are morning sedation and dry mouth.
This article was written by Broadgate Spine & Joint Clinic Rheumatologist Gerard Hall, and you can find out more about his work at http://www.broadgatespinecentre.co.uk/london-rheumatology/.