Costochondritis This is when the tissue in your rib cage gets inflamed because of arthritis, an injury, or infection. You may feel a sharp, aching pain or pressure in your sides. It could get worse after you work out or move your torso a lot. There’s no cure, and it can last up to a year. Over-the-counter acetaminophen (Tylenol) or ibuprofen can help. A warm compress or heating pad at the site of the pain will give relief, too.