They should be taken even if you are feeling well. Steroid tablets If your asthma gets really bad, your doctor might prescribe steroid tablets for between 3 and 14 days until the asthma is under control again. These tablets give a much higher dose of steroid than a steroid inhaler. They are particularly effective if you have a cold that has gone to your chest. A small number of people with severe asthma need to take steroid tablets for a longer period.
Inhaled steroids are very unlikely to cause side effects.
The dose of steroid is quite small and inhaled steroids go straight down to the airways so very little is absorbed into the rest of the body. This means that the possibility of side effects from steroid inhalers is very low. There is a small risk of a sore throat or you may feel a bit hoarse. Using your inhaler before brushing your teeth and using a spacer can help reduce this risk. Steroid tablets give a much higher dose of steroid than inhalers.