There are some simple strategies that can help someone in the throes of an acute anxiety attack:

• Sit with the person and offer calm physical reassurance
• Assure them it will pass and they will be OK
• Encourage them to breathe slowly and deeply as this aids relaxation
• Try and connect the person with sensory stimuli to ground them – ask what they can see, hear or smell, for example. 

The main aim is for the person to feel safe so they are able to calm down. Caregivers may want to discuss this with their child outside an attack, perhaps identifying an object or photograph that will help when they start to feel their fear response kicking in. The mental health charity Mind has more information. 

If someone is having a mental health crisis or emergency, immediate expert advice and assessment is needed. More on this from the NHS.

A child or young person who is exhibiting strong signs of anxiety, particularly if it is interfering with their quality of life, should be encouraged to seek medical help. If they are reluctant to do this, local youth counselling services may be available.

Educational institutes can provide contact information and often a referral, and a location search can be conducted. There are also several online resources and telephone helplines.