Fibromyalgia Fibromyalgia Is a Chronic Condition That Affects an Estimated 3-6

Fibromyalgia
Fibromyalgia is a chronic condition that affects an estimated 3-6% of the world's population. The disorder is characterized by both physiological and psychological symptoms, including nerve pain, fatigue, sleep and mood disturbances, headaches, bowel problems, and incontinence. The exact cause of fibromyalgia is unknown.
For some people, fibromyalgia symptoms begin after some sort of physical or psychological stress. However, for others, the onset of symptoms is gradual. Research has shown that genetics may play a part, but there is also evidence that environmental factors can contribute.
The wide variety of symptoms made it difficult to diagnose and treat for many years, though recent research has made some promising advances. Although a cure for fibromyalgia has not yet been developed, research has shown that some of the symptoms can be treated with pharmaceuticals, such as tricyclics or gabapentinoids, or non-pharmacological methods, such as meditation, mindfulness, and cognitive behavior therapy.
The most successful pharmacological treatment for fibromyalgia has been tricyclic antidepressants, such as amitriptyline and nortriptyline. These drugs increase the levels of the neurotransmitters serotonin and norepinephrine, which are often found at decreased levels in the brains of people who suffer from chronic pain. By boosting endorphins and relaxing muscles, tricyclics can ease some of the musculoskeletal pain felt by people with fibromyalgia.
Question: What is the author's main purpose for writing this passage.

A) To teach a lesson about the unintended effects of treating fibromyalgia with certain medications.
B) To persuade readers to learn more about fibromyalgia.
C) To entertain readers with a humorous story about fibromyalgia.
D) To inform readers of the symptoms, causes, and cures of fibromyalgia.