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Painkillers, also known as analgesics, are medications designed to alleviate pain without causing a loss of consciousness. They work by interacting with the body’s nervous system to either block or alter the perception of pain.
The effectiveness and potential for addiction vary significantly among different types of painkillers, which can be broadly categorized into non-opioid and opioid painkillers.
Non-opioid painkillers
Non-opioid painkillers include common over-the-counter medications such as aspirin, ibuprofen (Nurofen, Advil) and paracetamol (Panadol, Tylenol).
Aspirin and ibuprofen are non-steroidal anti-inflammatory drugs (NSAIDs), which relieve pain by inhibiting enzymes known as cyclooxygenases (COX).
These enzymes play a key role in the production of prostaglandins, compounds that mediate inflammation, fever and pain. By reducing prostaglandins’ synthesis throughout the body, NSAIDs effectively alleviate pain and decrease inflammation.
Paracetamol – also known as acetaminophen – is not considered an NSAID because it does not reduce inflammation. The mechanism of action is still under debate despite widespread use but recent evidence suggests that it does not impact COX enzymes. Instead, scientists think that it gets converted into a metabolite that, in the brain, acts on nerves that reduce the perception of pain.
Non-opioid painkillers generally have a low potential for addiction, making them suitable for managing mild to moderate pain.
However, misuse can still lead to adverse effects. For instance, excessive intake of paracetamol may cause severe liver damage. This is why it’s so important to adhere to recommended doses.
Opioid painkillers and addiction
Opioid painkillers, including morphine, oxycodone, codeine and fentanyl, operate on a different level. They are extremely effective, but come with significant side effects. Many opioid drugs, including heroin and opium are illegal, but they all function in similar ways.
Opioids mimic the pain-reducing chemicals naturally produced in our bodies, including endorphins and enkephalins. By binding to specific opioid receptors, endorphins and enkephalins act on nerves to reduce the perception of pain. Opioids tend to be more rapid at binding to these receptors than natural endorphins.
One of the brain circuits activated by opioids is the mesolimbic reward system. Opioids binding to receptors induces a euphoric feeling by causing a surge of dopamine, a neurotransmitter associated with pleasure and reward. This is at the heart of what makes them potentially addictive.
Regular use of opioids can lead to tolerance, where higher doses are required to achieve the same euphoric effect, and dependence, where the body adapts to the drug’s presence and experiences withdrawal symptoms without it.
Additionally, opioid use can lead to physical changes in the brain’s structure and function, particularly in regions critical to judgment, decision making and impulse control, further complicating the cycle of addiction.
Opioids are generally prescribed for severe pain, such as that resulting from surgery or cancer. However, the line between medically necessary use and the potential for misuse and addiction can become blurred, especially with long-term prescribing.
Australia and the USA, like many countries, have witnessed the consequences of opioid overprescribing, leading to increased rates of addiction, overdose and death.
It’s crucial for both healthcare providers and patients to be aware of the risks associated with opioid use and to consider alternative pain management strategies when possible.
This includes non-pharmacological approaches such as physical therapy, psychological support and lifestyle changes, which can be effective in managing chronic pain without the risk of addiction.
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*This article was generated by our custom AI service. Our service was built to focus on our archive of more than 15,000 factually correct science news stories and features. It also uses Open AI to help create the content. All generated content is fact checked by a trained science communicator and edited by our publishing team.
