There are three main types of painkiller: non-steroidal anti-inflammatory drugs (NSAIDS), paracetamol and opioids. Each works in a different way. Most people only need to take painkillers for a few days or weeks at most, but some people need to take them for a long time. You can buy some painkillers from pharmacies; this includes some NSAIDs, paracetamol and some weak opioids (codeine or dihydrocodeine). If you buy painkillers that contain weak opioids and you need to take them for more than three days you must discuss this with your pharmacist or doctor.
Painkillers are medicines that are used to treat pain. There are a large number of painkillers available and they all come in various different brand names. They can be taken:
- By mouth as liquids, tablets, or capsules.
- By injection.
- Via the back passage (rectum) as suppositories.
Some painkillers are also available as creams, ointments or patches.
Even though there are a large number of painkillers available, there are only three main types (each works in a different way). They are:
- Non-steroidal anti-inflammatory drugs (NSAIDS). Examples of NSAIDs include ibuprofen, diclofenac and naproxen. Aspirin is also an NSAID. However, it is mainly prescribed (in low doses) to help to keep the blood from clotting – for example, for people who have had a heart attack in the past.
- Weak opioids and strong opioids (sometimes called opiates). Examples of weak opioids include codeine and dihydrocodeine. Although commonly described as ‘weak opioids’, they are extremely effective analgesics often used to treat severe pain; however, they can lead to significant addiction and adverse effects, so should not be underestimated. Examples of strong opioids include morphine, oxycodone, pethidine and tramadol. Many people who need strong opioids are in hospital.
Different types of painkillers are sometimes combined together into one tablet – for example, paracetamol plus codeine (co-codamol).
In addition to the above, some antidepressants and antiepileptic medicines can be used to treat neuropathic pain. The rest of this leaflet does not discuss these types of medicines. For more information on them see the separate leaflet called Neuropathic Pain.