Gabapentinoids are a group of medications designed to help with neuropathic pain. Neuropathic pain is a specific condition where the nerve itself is damaged or impinged and is causing pain. This type of pain is typically a burning, stinging, electric type feeling. It can be difficult to describe. It is important to note that these medications are not usually used for common low back pain or pain that comes from muscles, ligaments, joints or tendons – particularly if there is no nerve trouble. Unfortunately, they don't work as well on those types of pain.
The medications work on calcium channels – these are little openings in nerves that allow calcium in and out. This calcium flowing in and out generates an electrical current, allowing pain signals to be transmitted. In damaged or irritated nerves, for some people, these calcium channels can become faulty and give ongoing or heightened pain signals.
Will this medication work for me? If your pain is neuropathic, and you may have these calcium channel issues, then gabapentinoid medications may be helpful for you.
Approximately 1 in 6 people who try these medications get significant pain relief (>50%). Other people may get a varied response from some benefit to none. It may not work for some people whose pain may not be from damaged or irritated nerves or those in whom calcium channels are not the main problem.
The main issue with pregabalin and gabapentin is that it has sadly been used for the wrong reasons in the past (such as for anyone with back pain for any reason) or at far too high doses – causing the medications to have a bad reputation. But like any tool – if used properly in the right person in the right way, it can be very helpful.
Can these medications be addictive? Gabapentinoids were originally designed to reduce seizures and help with depression. In some people, when they take the medication, it can make their mood significantly improve. This makes reducing or ceasing the medication more difficult. So this is not technically an addiction, but some people can use this medication inappropriately for reasons other than pain – such as to improve their mood or, in high enough doses, give a ‘high’.
Are there any side effects? Yes. While some people experience no side effects, the most common side effects some people experience are drowsiness or clouding of their thinking. For most people, these symptoms reduce as your body gets used to the medication. Some people may gain a small amount of weight (a few kgs on average) – however, others may have a stable weight.
Are there differences between gabapentin and pregabalin? Yes. Gabapentin is the older original drug – but it often has fewer side effects than pregabalin (Lyrica). However, it needs to be taken more regularly (three times a day) and is not onthe PBS – so the cost is generally slightly higher. Interestingly, if one does not work for you, they work differently enoughthat it may be trying the other one before saying these definitely do not work for you.
If you have further questions or want more information, talk to your pain team, your GP, or your pharmacist.