Asthma UK says children's lives are being put at risk by rules which prevent schools keeping spare inhalers on the premises.
Red tape currently bans schools from having additional inhalers for pupils because they are prescription only medicines.
The charity argues that a child who has forgotten their own inhaler, or has run out, is then being put at risk. It wants schools to be able to keep inhalers in the first aid room.
In a survey of more than 200 children by Asthma UK, nearly two-thirds reported having suffered an asthma attack at school, with one in five children claiming they found it "quite difficult" or "very difficult" to get access to their medication at school, whilst 55 per cent said they did not always know where their inhaler was, or how to get it.
Asthma UK's head of policy and public affairs, Emily Humphreys, said it it "crucial" the rules on inhalers in schools are changed: "These medicines are very safe but going without them can be very dangerous, so it is crucial the Medicines and Healthcare Products Regulatory Agency changes the rules and allows schools to keep a spare inhaler as a last resort."
She added that the "reality" was that there was very little staff could legally do if a child had an attack at school and did not have their inhaler. This, she says, "puts children at risk."
The armed forces and the Royal National Lifeboat Institution are currently exempt from the legislation that says inhalers cannot be kept in medical kits, and Asthma UK is asking for the same ruling for schools.
Dr Kevin Gruffydd Jones, from the Primary Care Respiratory Society, told The Mirror: "Asthma attacks are serious and children need access to inhalers as soon as possible.
"Introducing a spare inhaler for emergencies could prevent a serious asthma attack by getting prompt help for a child when it's needed."
Do you have a child with asthma?
Do you think schools should be allowed to keep spare inhalers?
Or should the responsibility lie with the parents and child?