Analgesics - Painkillers*
*Analgesic* = “An-” = without, “Algesia” = pain.
Meaning: *Medicine that reduces or removes pain* without causing loss of
consciousness.
Painkillers do not heal the injury. They only block or reduce the feeling of pain so
the brain does not sense it.
*I. How Pain Occurs in the Body - Simple Science*
1. Injury happens → cells get damaged
2. Damaged cells release a chemical called *Prostaglandins*
3. Prostaglandins send pain signals through nerves to the brain
4. Brain interprets the signal as “pain”
*How analgesics work*: Either they stop prostaglandin production, or they block
pain signals from reaching the brain.
*II. Types of Analgesics - 3 Main Categories*
**Type** **How it Works** **Examples** **Used For** **Important Note**
**1. Non-Opioid Analgesics** Reduce prostaglandin production. Also reduce
fever Paracetamol/Acetaminophen, Aspirin, Ibuprofen, Diclofenac Headache,
toothache, period pain, mild pain, fever Available OTC. Overdose can damage
liver/kidney
**2. Opioid Analgesics** Bind to pain receptors in brain. Block pain signals
completely Morphine, Codeine, Tramadol Severe pain after surgery, fractures,
cancer pain Prescription only. Can cause addiction/dependence
**3. Adjuvant Analgesics** Not painkillers originally, but help with nerve pain
Gabapentin, Amitriptyline Diabetic nerve pain, sciatica, shingles Only given by
doctors
*OTC* = Over The Counter = can be bought without prescription
*III. Common Non-Opioid Analgesics - Most Used at Home*
*1. Paracetamol / Acetaminophen - Panadol*
- *Action*: Acts on brain’s pain and temperature center
- *Benefit*: Best for mild pain, headache, fever. Does not irritate stomach
- *Risk*: Overdose = serious liver damage. More than 8 tablets in 24 hours is
dangerous
*2. NSAIDs = Non-Steroidal Anti-Inflammatory Drugs*
Examples: Aspirin, Ibuprofen/Brufen, Diclofenac/Voltaren, Mefenamic acid/
Ponstan
- *Action*: Reduce prostaglandins + reduce inflammation/swelling
- *Benefit*: Best when pain + swelling both present - sprains, joint pain,
*Analgesic* = “An-” = without, “Algesia” = pain.
Meaning: *Medicine that reduces or removes pain* without causing loss of
consciousness.
Painkillers do not heal the injury. They only block or reduce the feeling of pain so
the brain does not sense it.
*I. How Pain Occurs in the Body - Simple Science*
1. Injury happens → cells get damaged
2. Damaged cells release a chemical called *Prostaglandins*
3. Prostaglandins send pain signals through nerves to the brain
4. Brain interprets the signal as “pain”
*How analgesics work*: Either they stop prostaglandin production, or they block
pain signals from reaching the brain.
*II. Types of Analgesics - 3 Main Categories*
**Type** **How it Works** **Examples** **Used For** **Important Note**
**1. Non-Opioid Analgesics** Reduce prostaglandin production. Also reduce
fever Paracetamol/Acetaminophen, Aspirin, Ibuprofen, Diclofenac Headache,
toothache, period pain, mild pain, fever Available OTC. Overdose can damage
liver/kidney
**2. Opioid Analgesics** Bind to pain receptors in brain. Block pain signals
completely Morphine, Codeine, Tramadol Severe pain after surgery, fractures,
cancer pain Prescription only. Can cause addiction/dependence
**3. Adjuvant Analgesics** Not painkillers originally, but help with nerve pain
Gabapentin, Amitriptyline Diabetic nerve pain, sciatica, shingles Only given by
doctors
*OTC* = Over The Counter = can be bought without prescription
*III. Common Non-Opioid Analgesics - Most Used at Home*
*1. Paracetamol / Acetaminophen - Panadol*
- *Action*: Acts on brain’s pain and temperature center
- *Benefit*: Best for mild pain, headache, fever. Does not irritate stomach
- *Risk*: Overdose = serious liver damage. More than 8 tablets in 24 hours is
dangerous
*2. NSAIDs = Non-Steroidal Anti-Inflammatory Drugs*
Examples: Aspirin, Ibuprofen/Brufen, Diclofenac/Voltaren, Mefenamic acid/
Ponstan
- *Action*: Reduce prostaglandins + reduce inflammation/swelling
- *Benefit*: Best when pain + swelling both present - sprains, joint pain,
