Stress is the feeling of being under great strain and tension, anxiety is a strong feeling of unease and troubled and an episode of depression is extremely low level of self confidence and self esteem. Stress can deteriorate and initiate depression and anxiety both.
When a person is stressed out it becomes difficult for him to cope up with everyday problems, feelings of helplessness and hopelessness creep up and negative thoughts about the outcome of the events become frequent. Increased heart rate and blood pressure, sweating of palms or over all increased perspiration, drying of mouth and throat, quick movements and increase in muscle tension are few other symptoms of stress. Prolonged stress can easily descend to episodes of anxiety and depression.
Anxiety is a state where a person is intensely fearful and apprehensive about events and situation he or she is facing. Sufferer of anxiety cannot find a way out of the situation and finds difficult to cope up with life. Low self confidence, trembling hands, heavy sweating and palpitations are few symptoms of anxiety.
Feeling of loneliness, hopelessness, lack of concentration, extreme exhaustion, tiredness and fear of future are few symptoms of depression. Person suffering with this retreat in his own world, frequent mood swings are very much evident and either lack of appetite or there is substantial increase in appetite of the person under depression. Sleeplessness, sleep apnea, excessive sweating and indigestion are common physical symptoms of stress, depression and anxiety.
Stress is an outcome of a defense mechanism of our body designed to save human beings from physical threat also called as fight-flight response. This mechanism when perceives psychological stressors as potential threat. It rushes the blood to the muscles and brain to make us hyperactive, cholesterol and sugar levels are increased for higher energy and metabolism rate is reduced. If psychological stressors are not handled properly this stress response of the body can continue for weeks and months to cause stress disorder. Hormonal imbalance and hereditary factors may also cause stress.
Stress at work, relationship issues, trauma like death of loved one, 
abuse, intoxication, withdrawal, medication are few causes of anxiety. Evidences have shown that heredity and genetic reasons also cause anxiety. Though anxiety can occur anytime in any person environmental factors also play an important role in initiating anxiety. Some medical researches have shown improvement in some patients of anxiety when they were moved to different place for a longer period.
Depression too, like stress and anxiety is not caused by mere chemical imbalance in the brain. Mostly psychological stressors play a vital role in causing depression in any individual. Loneliness, lack of support from the society or family, financial stress, past trauma, drugs, alcohol abuse, family history of depression and chronic pain are few common causes of depression.
'Brahmi' is a nervine tonic that improves concentration, improves mental ability and works as effective anti-anxiety agent. It is an excellent memory supplement too. 'Ashwagandha' is Indian ginseng and a popular stress buster which promotes hormonal balance, improves metabolism, promotes sleep and increase energy levels. Combination of these two herbs as supplement has been found very effective since ages in resolving the disorder of stress, depression and anxiety.
