I believe morphine is addictive. What I mostly meant was those analgesics that do not require chemical processing before use.
Morphine is all-natural, and “unprocessed” (beyond extraction and purification), and highly addictive. (To my own surprise, it’s heroin that is the processed version.) Aspirin is effective straight from the willow inner bark (you can make a tea with it), or even eaten as fresh wintergreen. Most drugs are discoveries, not inventions.
>> Most drugs are discoveries, not inventions. <<
(Well, I should say that most drugs start OFF as discoveries. Then scientists find out why they work, and search for the chemical variant that is safest, has the fewest side effects, and is the most effective.)