Astraphobia, also known as astrapophobia, brontophobia, ceraunophobia, or tonitrophobia, is an abnormal fear of thunder and lightning or an unwarranted fear of scattered and/or isolated thunderstorms, a type of specific phobia. It is a treatable phobia that both humans and animals can develop.

A person with astraphobia will often feel anxious during a thunderstorm even when they understand that the threat to them is minimal. Some symptoms are those accompanied with many phobias, such as trembling, crying, sweating, panicked reactions, sudden feeling of using the bathroom, nausea, feeling of dread, insertion of the fingers in the ears, and rapid heartbeat

However, there are some reactions that are unique to astraphobia. For instance, reassurance from other people is usually sought, and symptoms worsen when alone. Many people who have astraphobia will look for extra shelter from the storm. They might hide underneath a bed, under the covers, in a closet, in a basement, or any other space where they feel safer. Efforts are usually made to smother the sound of the thunder; the person may cover their ears or curtain the windows.

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