Frequently Asked Questions
Understanding pain relief medication
What is pain?
Pain is one of the body's protective mechanisms. It acts as a warning sign to alert you to situations or actions that may be causing damage to your body so that you can act to avoid the situation or stop the action. Pain is the way your brain interprets information about a particular sensation that your body is experiencing. Signals are sent via nerve pathways to your brain.
Because perception and tolerance of pain can vary widely between individuals, that which is very painful for one person may be only moderately painful for another. In addition, the way in which your own brain interprets these signals can also be affected by many factors and so what is painful to you one day, may be less so on a different day.
Pain is usually categorised as being either acute or chronic.
Acute pain starts suddenly and tends to be short-lived, but may last up to 3 months. Acute pain has an identifiable cause and purpose and the pain gradually disappears through the process of normal healing.
Chronic or persistent pain by definition persists for more than six months, beyond the normal time of healing, and can sometimes last for years. Chronic pain may be the result of a specific injury or an ongoing medical problem or sometimes there may be no obvious cause. The pain associated with osteoarthritis is usually chronic pain.
Why is pain management important?
Being in constant pain will often affect other aspects of your life such as the ability to sleep soundly, the ability to work, it can lead to emotional distress and may cause strain on relationships. The treatment for chronic pain differs from that of acute pain. The medication choices that are appropriate for acute pain may not be the best choice for treating chronic pain. Some medications, because of their associated side effects, should only be used for the short term and as such are not recommended for treating chronic pain. Often non-medicated treatments can work as well as, if not better than, some medications for treating chronic pain.
Osteoarthritis (OA) can be a very painful condition. As someone with osteoarthritis, it is important that you work with your healthcare team to find the best combination of medicines and non-medicated treatments that will work for you, to minimise the pain and disability you experience. There are a number of non-medicated techniques for dealing with the pain of OA, which are detailed in the FAQ called “Non-Medicated Pain Management” which you should review if you haven’t already done so. However it is also important to understand what types of medications are recommended to be used to prevent and to treat the pain of OA.
There are a number of medicines your doctor may choose to recommend for you and their choice of medications will depend on how severe your pain is, any other medicines you might be taking, and any other health conditions you may have. Often they will recommend a combination of medications to best treat both the pain and inflammation that is associated with OA.
Pain relieving medications (analgesics)
Pain relieving medications work by inhibiting or blocking the brain’s perception of pain. They don’t stop the damage that is causing the pain but they do reduce the sensations that are relayed via the nervous system back to the pain centre of the brain, enough so that functions of daily living can still be performed.
Potential Side Effects
Any medication that has a therapeutic effect also has the potential to cause unwanted or adverse side effects. To find out more about the potential side effects of the medications you take, ask your pharmacist for a Consumer Medication Information leaflet and discuss with them the information contained within it.
The latest RACGP guidelines for the management of knee and hip osteoarthritis does not recommend either for or against paracetamol.
Paracetamol is usually well tolerated, so a short term trial may be warranted however if no benefit is experienced there is no reason to continue. If you have taken paracetamol previously and found it to provide clear benefit it is reasonable to continue at the lowest dose that will still manage your pain.
If you know that certain activities tend to cause you pain, like taking the dog for a walk, take your dose of paracetamol half an hour before
commencing the activity and repeat the dose again at the appropriate interval. This way you can maintain better control of your pain.
Slow-release tablets are now available so the dosage can be taken fewer times a day. To prevent accidentally taking too much
paracetamol, it is important that you check the list of active ingredients on the label of any other over-the-counter medicines you intend taking, and speak to your pharmacist about them, as many products do contain paracetamol in combination such as cold and flu medicines.
NSAIDs (Non-steroidal Anti-inflammatory Drugs)
In addition to relieving pain, NSAIDs also reduce inflammation and swelling so are very effective treatments for osteoarthritis.
Due to their potential for side effects,
especially gastrointestinal, renal and cardiovascular effects, these medications may not be appropriate for some people.
Common brand names for over-the-counter NSAIDs include Nurofen® or Voltaren®. In recent years, a new group of prescription only NSAIDs has appeared on the market
(eg Celebrex® and Mobic®) which are said to be easier on the gut in some people. The doctor will still usually closely monitor blood
pressure and kidney function of patients whilst they are taking NSAIDs to prevent complications.
NSAIDs can also interact with certain other medications and some health conditions, therefore they are usually recommended only for short bursts of treatment when other non-pharmacological pain relief is inadequate, and at the lowest effective dose.
For those experiencing severe acute pain that has not responded to other medications (and for those who haven’t been able to tolerate
other medications) the next choice in pain relievers are oral opioids, such as codeine.
Opioids are very effective pain relievers although they also tend to have significant and potentially harmful adverse effects, therefore they are not considered as an appropriate treatment for chronic pain. They may be considered for short intervals, and only if other alternatives have proven ineffective or inappropriate.
Again, your doctor will usually closely monitor opioid analgesic use to ensure the benefits of treatment continue to outweigh the risks of adverse events.
An Intra-articular injection (IA) of corticosteroid directly into the joint is sometimes appropriate for short term symptom relief of an acutely painful, swollen joint. The injection of a steroid reduces inflammation in the joint and therefore reduces pain. There is the potential that repeated steroidal IA injections can result in possible cartilage damage so the number of injections a patient receives is generally limited to three times per year for large weight bearing joints (eg knees and hips) and four times a year for smaller joints (eg toes, fingers, etc).
Anti-inflammatory Creams & Gels
Massaging a cream or gel containing an NSAID into the skin over an affected joint allows the medication to be absorbed into the tissue immediately surrounding the joint resulting in an increased concentration of the drug in the vicinity of the painful joint.
The benefit of using these creams and gels directly on the skin over NSAIDs in tablet form, is that the dose of active drug in the bloodstream is lower and by-passes the stomach meaning there is a much lower risk of gastrointestinal side effects. There is also potentially a lower risk of medication interactions.
Creams and gels are often recommended for short term use in the treatment of pain associated with knee osteoarthritis. Their
effectiveness is not increased by combining them with oral medications but it could increase your risk of adverse effects.
There is a large variability in the quality and availability (or lack thereof) of evidence both for or against the use of most supplements in osteoarthritis.
The RACGP guidelines for the management of knee and hip osteoarthritis suggests that individuals should make informed decisions about the potential benefits versus the known risks of complementary pain relieving therapies. This is often easier said than done because of the vast amount of conflicting information in the mass media.
It is recommended that you discuss carefully with your pharmacist or GP any supplement you are thinking of trying especially in regards efficacy, any potential for interaction with other medications you are taking or their known side effects.
The RACGP guidelines also caution that if no benefit is experienced within 4-6 weeks the supplement should be ceased.
IMPORTANT: This information has been provided to give a brief description of some of the medications you may come across in relation to osteoarthritis. It is not designed to replace the advice or recommendations given to you by your doctor or other members of your supervising healthcare team. Please consult your GP or health care provider if you have a specific query in regards any medications.