How long would butane stay in the body's system if a small amount inhaled?

Depends: Literature review states few minutes to 2 hours. Purposeful exposure or inhalation of butane is very dangerous and can lead to sudden death. There is a very thin margin between purposeful exposure to produce a drug high and sudden death. DO NOT expose yourself to purposeful inhalation. Any symptoms such as chest pain, palpitations, difficulty breathing....seek care ASAP in ER