When patients are emotionally affected in the form of nervousness or fear, it can lead to vasovagal collapse. This is the anticipation of pain during administration that activates the parasympathetic nervous system while inhibiting the orthosympathetic nervous system. What results is a dilation of arteries in muscles which can lead to a reduction in circulating blood volume inducing a temporary shortness of blood flow to the brain. Notable symptoms include restlessness, visibly looking pale, perspiration and possible the loss of consciousness. In severe cases, clonic cramps resembling an epileptic insult may occur.