A person who has generalized anxiety may feel irritable or restless, have tense muscles, shortness of breath, heart palpatations, sweating, dizziness, and be easily fatigued. Anxiety Disorder Caused by Other General Medical Conditions Patients with cancer may experience anxiety that is caused by other medical conditions. Patients who are experiencing severe pain feel anxious, and anxiety can increase pain. The sudden appearance of extreme anxiety may be a symptom of infection, pneumonia, or an imbalance in the body's chemistry. It may also occur before a heart attack or blood clot in the lung and be accompanied by chest pain or trouble breathing.
Anxiety is a direct or indirect side effect of some medications.
Some medications can cause anxiety, while others may cause restlessness, agitation, depression, thoughts of suicide, irritability, or trembling. Certain tumors may cause anxiety or produce symptoms that resemble anxiety and panic by creating chemical imbalances or shortness of breath. It may be difficult to distinguish between normal fears associated with cancer and abnormally severe fears that can be classified as an anxiety disorder. Treatment depends on how the anxiety is affecting daily life for the patient. Anxiety that is caused by pain or another medical condition, a specific type of tumor, or as a side-effect of medication, is usually controlled by treating the underlying cause.