Anxiety is defined as a consistent state of fear which may or may not be associated with a specific object or situation. Suffers may experience physiological changes such as a fast heartbeat and rapid breathing causing significant social or occupational impairment.

Western psychiatry defines major depression as a persisting pattern of severe depressive episodes, lasting for at least two weeks, accompanied by at least four additional symptoms including: changes in appetite, weight loss or gain, sleep disturbance, fatigue, feelings of worthlessness or guilt, difficulty thinking, suicidal thoughts . Major depressive disorder is also known as unipolar depression to distinguish it from bipolar disorder, or manic depression.

Reactive depression occurs due to stressful life events and "endogenous" depression describing cases without an external cause but arising from changes in the brain.

The Western medical explanation for the success of acupuncture in the treatment of depression is that the acupuncture points stimulate the central nervous system (CNS),. release chemicals into the muscles, brain and spinal cord, thus promoting the body's own natural healing abilities. The NIH says, "Studies have shown that acupuncture may alter brain chemistry by changing the release of neurotransmitters and neurohormones in a good way."

Acupuncture treatments cannot alter an individuals circumstances, but can prove useful in combating stress. From an Eastern perspective acupuncture is primarily concerned with regulating our life force, called 'qi' .Treatment with acupuncture has a relaxing, calming and tranquilising effect that is especially helpful for people suffering from stress. It can relieve feelings of anxiety and depression, which can be a serious handicaps for people coping with life situations. Acupuncture can also improve one's sense of self-confidence and well-being and relieve the tension associated with chronic stress and anxiety.