Methamphetamines such as ice increase the heart rate which can cause people to feel out of breath. Some people may suddenly feel very frightened or paranoid (suspicious) which can trigger panic attacks. Other common symptoms include restlessness, shaking, dizziness, sweating, dry mouth, muscle aches, headaches, feeling sick in the stomach or vomiting. These symptoms can leave people feeling agitated or nervous, particularly as the drug starts to wear off. If these symptoms persist for several days, or a few weeks, it may be a sign that an anxiety disorder is present. Click here for tips about how to help someone who is having a or experiencing other side effects.