Inhaled corticosteroids (ICSs) are widely used in chronic obstructive pulmonary disease (COPD). Since inflammatory processes play a key role in the pathogenesis of the disease and ICSs have been shown to be very effective in controlling asthma, their use in COPD patients has become widespread. However, their efficacy in COPD is more limited than in asthma, since the type of inflammation in COPD is predominantly neutrophilic and resistant to corticosteroids. ICSs have not been shown to prevent disease progression or reduce mortality in clinical trials. By contrast, these agents reduce exacerbations and improve both symptoms and quality of life in selected patients, particularly those with bronchial reversibility. Since ICSs are not harmless drugs, clinicians should make every effort to distinguish patients who will benefit from ICS treatment from those who will not. Side effects of ICSs may be both local and systemic, with most of them being dose dependent. A potential increase in the risk of pneumonia, diabetes, dysphonia or candiadiasis, among other complications, should be considered when prescribing these drugs in patients who usually have several comorbidities. Hence, it is important to identify those patients in whom the best risk-to-benefit ratio can be achieved and to use the most appropriate ICS dose with the least incidence of side effects.