The UK’s National Institute for health and Care Excellence (Nice) has introduced a guide for asthma patients that aims to help them make more environmentally friendly choices about the kind of inhaler to use.

Some inhalers are greener than others. Metered dose inhalers, for example, use hydrofluorocarbons (HFCs) – potent greenhouse gases that persist in the atmosphere and contribute to global warming – as propellants. Others, such as dry powder inhalers, have a much lower carbon footprint as they don’t contain HFCs. Despite this, metered dose inhalers account for 70% of prescription sales in the UK, and more than 26 million were prescribed in 2016–17. Nice says in many cases – though admittedly not all – patients using metered dose inhalers could control their symptoms just as effectively with dry powder ones. It points out that in other countries use of metered dose inhalers are lower – such as in Sweden where they make up just 10% of inhaler sales.

‘People who need to use metered dose inhalers should absolutely continue to do so,’ said Gillian Long, Nice’s deputy chief executive, in a statement. ‘But if you have the choice of a green option, do think about the environment. Cutting carbon emissions is good news for everyone, especially those with respiratory conditions.’