Science
How does a painkiller work?
A painkiller works by interrupting the pain signals your body sends to your brain. Some block the chemicals that flag injury at the source, while others act in the brain and spinal cord to dull how strongly pain is felt.
See it in motion.
Watch a 2-minute animated lesson that shows exactly how a painkiller works.
Step by step
- 1Pain is a signal sent from an injury to the brain.
- 2Drugs like ibuprofen block the chemicals that trigger pain at the site.
- 3Opioids act on the brain and spinal cord to reduce pain perception.
- 4Some reduce inflammation, easing the cause as well as the signal.
- 5Different painkillers suit different kinds and strengths of pain.
Frequently asked questions
- How do painkillers stop pain?
- Either by blocking the chemicals that signal injury where it happens, or by acting on the brain and spinal cord to dull how pain is perceived.
- How is ibuprofen different from opioids?
- Ibuprofen reduces inflammation and pain signals at the source; opioids work in the nervous system to lower pain perception and are far stronger and riskier.
- Why don't painkillers fix the injury?
- Most only quiet the pain signal or inflammation; the underlying damage still has to heal on its own.