"There is some evidence that relaxation techniques may be an effective part of an overall treatment plan for some disorders, including anxiety, depression, headaches, and pain. Research results for high blood pressure, asthma, nausea, fibromyalgia, irritable bowel syndrome, heart disease, insomnia, temporomandibular disorder, ringing in the ears, smoking cessation, overactive bladder, nightmares, and hot flashes have been mixed or unclear, or more research is needed. Relaxation techniques are generally considered safe for healthy people, but there have been rare reports that certain techniques might cause or worsen symptoms in people with epilepsy or certain psychiatric conditions, or with a history of abuse or trauma. People with heart disease should talk to their doctor before doing progressive muscle relaxation. Relaxation techniques are often used as part of a treatment plan and not as the sole treatment for potentially serious health conditions. Do not use relaxation techniques as a replacement for conventional care or to postpone seeing a doctor about a medical problem. Tell your health care providers about any complementary and alternative practices you use."