Do the treatments differ between allopaths, osteopaths, naturopaths, and chiropracters?

Yes they differ: Allopaths are MDs who use conventional treatments such as drugs and surgery. Osteopaths are DOs who use the above but are trained in manipulation of the body and are a bit slower to use drugs. Naturopaths us natural approaches such as supplementation, nutrition, etc. Chiropractors adjust the musculoskeletal system to facilitate the flow of impulses through the nervous system. Peace and health.

YES, a great deal: Allopaths practice conventional western medicine,relying primarily on drugs & surgery for treatment. Many osteopaths practice allopathic medicine but the root of osteopathy is gentle manipulation of bones & many osteopaths still include this. Naturopaths primarily utilize nutritional supplements, herbs & homeopathy,whereas chiropractors use various manipulative therapies & often use supplements.

Yes: They all have different approaches to treatment.