(Aging Untold) - Millions of Americans live with chronic pain.

The epidemic is often hidden behind closed doors as patients suffer in silence, according to research published in the "Journal of Primary Care & Community Health." Chronic pain, such as back pain, arthritis and headaches, including migraines, is often described as aching, burning, shooting or throbbing.

For those who cannot get relief from traditional pain management methods, some in the medical community are promoting ketamine infusion as a possible solution.