Ten percent of Americans, and possibly more, suffer from the fear of needles, the extreme fear of being punctured by a hypodermic needle. In its most extreme form, vasovagal, the sufferer fears the sight, thought, or feeling of needles or needle-like objects. The primary symptom of vasovagal fear is fainting due to a decrease in blood pressure but usually also includes sweating, nausea, pallor, tinnitus, panic attacks, initially high blood pressure and heart rate followed by a plunge in both at the moment of injection. Vasovagal needle phobia is among the most dangerous of the phobias for two reasons. First, a severe drop in blood pressure brought on by the vasovagal shock reflex can cause death; and second, people who suffer from trypanophobia tend to avoid doctors, with obvious consequences.