Anxiety is, according to the Mental Health Foundation, a “type of fear usually associated with the thought of a threat or something going wrong in the future, but can also arise from something happening right now”.

The severity of the symptoms can vary from person to person, and can include:

Restlessness
A sense of dread
Feeling constantly “on edge”
Difficulty concentrating
Irritability
Dizziness
Tiredness
Shortness of breath
Nausea
Panic attacks
Heart palpitations

While anxiety can last for long periods of time and cause serious distress, it can be effectively treated through counselling, medication and self-help techniques, though not all work for all sufferers.

Stephen Buckley, from the mental health charity Mind, says: “A lot of people don’t understand what anxiety is and how serious it is. It can have a devastating impact on their life.

“But it is a very common problem and people shouldn’t feel hopeless. With the right help things will get better.”

Sadie Frost on her “crippling” anxiety and panic attacks: “It’s a scary thing to talk about”