It’s natural to feel nervous or anxious before taking a big test or giving a speech. But with anxiety disorders, feelings of worry, panic or fear are unusually intense. And they don’t go away.

There are different types of anxiety disorders, notes the National Institute of Mental Health (NIMH)*. Common types include generalized anxiety disorder, panic disorder and phobia-related disorders.

Generalized anxiety disorder (GAD)

With GAD, you may feel as if your worries are out of control. You may feel excessively anxious about your health, work, social life and everyday situations. Symptoms such as these may be present most days for 6 months or longer:

• Feeling restless, wound-up or on-edge
• Being easily fatigued
• Trouble concentrating
• Being irritable
• Muscle tension
• Trouble controlling feelings of worry
• Sleep problems, such as trouble falling or staying asleep

Panic disorder

Panic disorder includes sudden periods of intense fear, known as panic attacks. Panic attacks may occur unexpectedly or could be a reaction to something. During a panic attack:

• You may have heart palpitations. Your heartbeat may feel rapid or pounding.
• You may sweat, tremble or shake.
• You may feel like you can’t breathe or are choking.
• You may have feelings of impending doom.
• You may feel out of control.

If you have panic disorder, you may live in constant worry over when the next panic attack may occur. You may limit activities and interactions. This may interfere with everyday life.

Phobia-related disorders

People with phobias have intense fear of certain things or situations. Some common phobias include fear of flying, heights, animals such as snakes or spiders, getting shots or seeing blood. People also may be fearful of social situations or even just being out in public or outside of their homes.

It’s natural to feel somewhat fearful of danger. But with a phobia, you may feel excessively fearful of the object or situation — more so than makes sense compared to the actual risk. You may feel such intense anxiety when confronted with the object or situation that you may take extreme steps to avoid it.