There are many reasons why back pain can occur, but the most common are muscle and ligament strains and arthritis. Those suffering from backaches often describe their symptoms as follows: Dull ache or pain in lower back, discomfort while moving around, walking or standing. Soreness to the touch. Doan's Extra Strength Caplets provide fast and effective pain relief for minor backache pain. Each caplet contains a pain reliever called Magnesium Salicylate Tetrahydrate, a nonsteroidal anti-inflammatory drug (NSAID).