What are painkillers?
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:
1. Paracetamol
Also known as acetaminophen, paracetamol is one of the commonly used analgesics to control fever. However, this medicine is also used to relieve pain along with being the first line of treatment for high body temperature.
How it works: The exact action mechanism of this class of drug is still debated. However, it is believed to inhibit the synthesis of prostaglandins in the central nervous system (CNS). Prostaglandins are hormones which are released at the site of injury or infection and play a key role in controlling inflammatory response.
Side-effects: It is one of the best tolerated medicines. However, side-effects such as allergies are reported in certain cases. But an overdose of this medicine can lead to liver damage (hepatotoxicity).
Hence, always consult your doctor before taking this medicine to know the right dosage and prevent its side-effects.
2. Non-steroidal anti inflammatory drugs (NSAIDs)
NSAIDs are the common painkillers which reduce pain, fever and inflammation. But unlike other anti-inflammatory medicine, they do not contain steroids. These medicines are the largest group of over the counter painkillers which are used to treat different types of pain like headache, period pain and toothache.
How it works: NSAIDs inhibit the action of the enzymes known as cyclooxygenases or COX enzymes, which play a key role in the production of prostaglandins. However, these drugs are non-specific in their action.
Side-effects: The main safety concerns to be aware of when using NSAIDs are complications with gastrointestinal tract, kidney, heart, blood, liver and allergic reactions. This is mainly because these drugs inhibit the action of COX-1 enzyme which affect the GI tract. Moreover, these drugs can interact with various medicines.
These drugs are commonly used as over the counter (OTC) medicines to treat pain and fever. However, taking NSAIDs is shown to increase the incidence of heart attack and stroke. Hence, avoid using these drugs without your doctor’s advice.
3. Opioids
Opioids are undoubtedly one of the strongest analgesics available in the market. These are commonly used to treat moderate to severe pain which could be acute or chronic. It is also used to fight pain during cancer treatment. Tramadol is one of the most commonly used drug to treat moderate to severe pain, especially for long-term pain relief.
How it works: This class of drugs acts by suppressing the neurotransmission in the central nervous system, which helps in alleviating pain. This is achieved due to the binding of the drugs to the opioid receptors, more specifically μ receptor, present in the brain.
Side-effects: The use of opioids have increased significantly over the last decade and thus, the frequency of adverse drug reactions. The most common side effects of opioids include constipation, nausea, vomiting, sedation, urinary retention, pruritus and depression.
As these drugs are mostly used to manage chronic pain, the risk for opioid dependence, leading to its abuse and misuse, has increased. This is why you check with your doctor about the pros and cons of these drugs before use to prevent dependence on these drugs.
Which painkiller is usually prescribed?
The type of painkiller your doctor will prescribe depends upon:
- The type of pain you have.
- Any other health problems you may have.
- How severe your pain is.
- The possible side-effects of the medicines.
Paracetamol is normally prescribed if your pain is not too serious and you do not have inflammation.
NSAIDs are generally prescribed for people who have pain and inflammation – for example, if you have pain in your joints (arthritis) or muscles (back pain). This is because there is likely to be some inflammation present and NSAIDs work well to treat pain as well as inflammation. NSAIDs have a number of possible side-effects and they are not suitable for everyone. For example, they are not suitable for people who have or have had stomach ulcers. In this case a doctor may prescribe a safer medicine (paracetamol) even though it may not work as well. NSAIDs can be used with heat and ice treatment in joint, muscle or ligament injuries.
Weak opioids are usually prescribed for more severe pain, or if you have tried paracetamol and/or ibuprofen and they have not worked.
Stronger opioids are normally used to treat severe pain – for example, cancer-related pain, pain after an operation, or if you have had a serious injury.
Anti-inflammatory medicines used as a cream (topical painkillers) are mainly used to treat pain in your soft tissues and muscles.
What is the usual length of treatment?
Like all medicines, painkillers should be taken for the shortest period of time possible, in the lowest dose that controls your pain. This is to help avoid any side-effects. Most people only need to take painkillers for a few days (for example, for toothache) or weeks (having pulled a muscle). However, some people have painful conditions and need to take painkillers on a long-term basis. Examples include people with rheumatoid arthritis, osteoarthritis, or chronic back pain.