Tension headache, stress headache, or tension-type headache (TTH), is the most common type of primary headache. The pain usually radiates from the lower back of the head, the neck, the eyes, or other muscle groups in the body typically affecting both sides of the head. Tension-type headaches account for nearly 90% of all headaches. Pain medications, such as paracetamol and ibuprofen, are effective for the treatment of tension headache. Tricyclic antidepressants appear to be useful for prevention. Evidence is poor for SSRIs, propranolol and muscle relaxants. The 2016 Global Burden of Disease study revealed that TTHs affect about 1.89 billion people and are more common in women than men (30.8% to 21.4% respectively). TTH was most prevalent between ages 35 and 39. Despite its benign character, tension-type headache, especially in its chronic form, can impart significant disability on patients as well as burden on society at large. In 2016, the global burden of TTH was reported to be 7.2 million years of life lived with disability (YLDs). The YLD was calculated using TTH prevalence and average time spent with TTH multiplied by percentage health loss caused by TTH (3.7%). Source: Wikipedia (en)