Stress can come from any situation or thought that makes you feel frustrated, angry, or anxious. What is stressful to one person is not necessarily stressful to another.

Anxiety is a feeling of apprehension or fear. The source of this uneasiness is not always known or recognized, which can add to the distress you feel.

Stress is a normal part of life. In small quantities, stress is good -- it can motivate you and help you be more productive. However, too much stress, or a strong response to stress, is harmful. It can set you up for general poor health as well as specific physical or psychological illnesses like infection, heart disease, or depression. Persistent and unrelenting stress often leads to anxiety and unhealthy behaviors like overeating and abuse of alcohol or drugs.

Emotional states like grief or depression and health conditions like an overactive thyroid, low blood sugar, or heart attack can also cause stress.

Anxiety is often accompanied by physical symptoms, including:

• Twitching or trembling
• Muscle tension, headaches
• Sweating
• Dry mouth, difficulty swallowing
• Abdominal pain (may be the only symptom of stress, especially in a child)

Sometimes other symptoms accompany anxiety:

• Dizziness
• Rapid or irregular heart rate
• Rapid breathing
• Diarrhea or frequent need to urinate
• Fatigue
• Irritability, including loss of your temper
• Sleeping difficulties and nightmares
• Decreased concentration
• Sexual problems

Anxiety disorders are a group of psychiatric conditions that involve excessive anxiety. They include generalized anxiety disorder, specific phobias, obsessive-compulsive disorder, and social phobia.

Certain drugs, both recreational and medicinal, can lead to symptoms of anxiety due to either side effects or withdrawal from the drug. Such drugs include:

• ADHD medications
• Alcohol
• Amphetamines
• Bronchodilators for asthma
• Caffeine
• Cocaine
• Cold remedies
• Decongestants
• Diet pills
• Nicotine
• Thyroid medications
• Tricyclic antidepressants

A poor diet -- for example, low levels of vitamin B12 -- can also contribute to stress or anxiety. Performance anxiety is related to specific situations, like taking a test or making a presentation in public. Posttraumatic stress disorder (PTSD) develops after a traumatic event like war, physical or sexual assault, or a natural disaster. People with generalized anxiety disorder experience almost constant worry or anxiety about many things on more than half of all days for 6 months. Panic disorder or panic attacks involve sudden and unexplained fear, rapid breathing, and increased heartbeat.

In very rare cases, a tumor of the adrenal gland (pheochromocytoma) may be the cause of anxiety. The symptoms are caused by an overproduction of hormones responsible for the feelings of anxiety.

The most effective solution is to find and address the source of your stress or anxiety. Unfortunately, this is not always possible. A first step is to take an inventory of what you think might be making you "stress out":

• What do you worry about most?
• Is something constantly on your mind?
• Does anything in particular make you sad or depressed?
• Keep a diary of the experiences and thoughts that seem to be related to your anxiety. Are your thoughts adding to your anxiety in these situations?

Then, find someone you trust (friend, family member, neighbor, clergy) who will listen to you. Often, just talking to a friend or loved one is all that is needed to relieve anxiety. Most communities also have support groups and hotlines that can help. Social workers, psychologists, and other mental health professionals may be needed for therapy and medication.

Also, find healthy ways to cope with stress. For example:

• Eat a well-balanced, healthy diet. Don't overeat.
• Get enough sleep.
• Exercise regularly.
• Limit caffeine and alcohol.
• Don't use nicotine, cocaine, or other recreational drugs.
• Learn and practice relaxation techniques like guided imagery, progressive muscle relaxation, yoga, tai chi, or meditation. Try biofeedback, using a certified professional to get you started.
• Take breaks from work. Make sure to balance fun activities with your responsibilities. Spend time with people you enjoy.
• Find self-help books at your local library or bookstore.

Your doctor can help you determine if your anxiety would be best evaluated and treated by a mental health care professional.

Call 911 if:

• You have crushing chest pain, especially with shortness of breath, dizziness, or sweating. A heart attack can cause feelings of anxiety.
• You have thoughts of suicide.
• You have dizziness, rapid breathing, or racing heartbeat for the first time or it is worse than usual.

Call your health care provider if:

• You are unable to work or function properly at home because of anxiety.
• You do not know the source or cause of your anxiety.
• You have a sudden feeling of panic.
• You have an uncontrollable fear -- for example, of getting infected and sick if you are out, or a fear of heights.
• You repeat an action over and over again, like constantly washing your hands.
• You have an intolerance to heat, weight loss despite a good appetite, lump or swelling in the front of your neck, or protruding eyes. Your thyroid may be overactive.
• Your anxiety is elicited by the memory of a traumatic event.
• You have tried self care for several weeks without success or you feel that your anxiety will not resolve without professional help.

Ask your pharmacist or health care provider if any prescription or over-the-counter drugs you are taking can cause anxiety as a side effect. Do not stop taking any prescribed medicines without your provider's instructions.

Your doctor will take a medical history and perform a physical examination, paying close attention to your pulse, blood pressure, and respiratory rate.

To help better understand your anxiety, stress, or tension, your doctor may ask the following:

• When did your feelings of stress, tension, or anxiety begin? Do you attribute the feelings to anything in particular like an event in your life or a circumstance that scares you?
• Do you have physical symptoms along with your feelings of anxiety? What are they?
• Does anything make your anxiety better?
• Does anything make your anxiety worse?
• What medications are you taking?

Diagnostic tests may include blood tests (CBC, thyroid function tests) as well as an electrocardiogram (ECG).

If the anxiety is not accompanied by any worrisome physical signs and symptoms, a referral to a mental health care professional may be recommended for appropriate treatment.

Psychotherapy such as cognitive-behavioral therapy (CBT) has been shown to significantly decrease anxiety. In some cases, medications such as benzodiazepines or antidepressants may be appropriate.

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Lubit R, Rovine D, Defrancisci L, Eth S. Impact of trauma on children. J Psychiatr Pract. 2003; 9(2): 128-138.

Ahmed SM, Lemkau JP. Psychosocial influences on health. In: Rakel RE, ed. Textbook of Family Medicine. 7th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 4.