How long a Ventolin inhaler lasts will vary depending on the severity of a patient's asthma and how well the condition is controlled. Ventolin inhalers used for well-controlled, mild asthma might last up to a few months, whereas asthma sufferers with more severe asthma will find that their inhaler only lasts a few weeks (Beat Asthma, 2022; NHS Grampian, 2023). How your inhaler is stored and its expiration date will also affect how long it lasts for you (Bass, P., 2021; Healthline, 2023). Your doctor or healthcare professional will be able to advise you on the appropriate dosage of Ventolin (salbutamol) to treat your individual case of asthma.