How to use wild watermelon? "Wild watermelon" is thumb-sized, grows in the western desert, is highly toxic and can only be used externally. Don't put wild watermelons where children can reach them to avoid accidental poisoning. It is recommended that patients with rheumatism and rheumatoid arthritis try it. Soak "Wild Watermelon" in high-alcohol liquor, and the alcohol content should be above 52 degrees. Apply it once every morning when you get up and once before you go to bed at night. It is very effective.