PMS (or PMT) is caused by hormonal changes and imbalances during the menstrual cycle and can last from one or two days to two weeks. Symptoms may include erratic behaviour, moodiness, irritability, anger, depression, tearfulness, breast distension and abdominal bloating.
From a Chinese medicine perspective, Qi (energy) builds up in the body just before the period begins (like pressure in a pressure cooker), and is released once the period arrives. However, when a woman suffers from PMS it is a sign that there is an excessive accumulation of Qi and acupuncture can be an effective way to regulate this build up of pressure and alleviate symptoms.