Disclaimer: I am not giving medical advice; I am not medically qualified; do your own research and take responsibility for your actions.

I am not sure whether this species is Lactuca serriola, ‘prickly lettuce’, or L. virosa, however, I lean towards L. serriola. Also known as ‘opium lettuce’, although not addictive. The wonderful thing is that it grows in the wild, and manages Perth’s hot dry spring and summers, setting seed in late summer-autumn. I collect the seed for a rainy day. Look for it in your neck of the woods, and see if you can accumulate a store of this natural pain reliever for when you might need it.