Depends. The side effects of inhaled steroids depend on the dose, and how long they are used. The side effects can include osteoporosis, decreased growth velocity in children, thrush, and rarely, cataracts, bruising/skin atrophy, fractures, and adrenal insufficiency. However, these risks must be weighed against the danger of uncontrolled asthma or copd. Definitely discuss any concerns with your provider.
Mostly benign. Most common is a change in voice quality. There is slight increase in the incidence of osteoporosis but this is a very small risk. Patient who have COPD and use inhaled steroids are more likely to get bronchitis but this does not appear to be associated with poor outcome. If you use inhaled steroids for asthma, and your symptoms are controlled there is good evidence that the dose can be decrease.