Two out of three people who had emergency treatment for an asthma attack in 2018 did not have an emergency follow-up appointment with their GP practice, Asthma UK said.
NICE guidance recommends that patients who experience an asthma atttack should have a follow-up appointment with their GP or practice nurse within two days.
The charity's annual report on asthma care in the UK surveyed more than 10,000 patients and found that one in four needed emergency care after an asthma attack. Just 64% of these respondents were offered a GP practice appointment within the two-day window, the survey found.
The charity warned that urgent follow-up care was a key step in avoiding further asthma attacks and emergency admissions - with one in six people receiving emergency asthma treatment experiencing an attack within the following two weeks.
Asthma UK clinical lead, GP Dr Andy Whittamore, said: 'It’s gravely concerning that so many people with asthma could be missing out on life-saving follow-up care. Once you have had an asthma attack, you are much more vulnerable to having another one.
'This is because there is more inflammation in your lungs so you are more sensitive to any asthma trigger such as cold weather or pollution. It is vital people see their doctor so they can get the help they need to avoid another asthma attack.
'Patients are slipping through the cracks because NHS systems are letting them down. It is vital that the NHS embraces technology to ensure patients get joined up care. It needs to put systems in place so that patients are automatically given follow-up care if they have had emergency treatment. It could save lives.'