NSAIDs are among the most often used drugs worldwide. Numerous NSAID users are at risk for developing gastrointestinal complications. The purpose of this review was to identify and stratify risk factors for gastrointestinal complications in NSAID users documented in guidelines and consensus agreements, and to collect recommendations regarding over-the-counter (OTC) NSAID use. To facilitate this, a PubMed search from 1 January 1999 until 1 March 2009 was performed, resulting in the inclusion of nine English-language guidelines in our analysis. Risk factors were defined as 'definite' if mentioned in all guidelines; otherwise they were defined as 'controversial' risk factors. 'Definite' risk factors were a history of (complicated) peptic ulcer disease, older age (cut-off range 60-75 years), concomitant anticoagulant or corticosteroid use and multiple NSAID use, including low-dose aspirin (acetylsalicylic acid). 'Controversial' risk factors were high-dose NSAID use, concomitant clopidogrel or selective serotonin reuptake inhibitor use, a history of gastrointestinal symptoms, rheumatoid arthritis disability and cardiovascular disease. Infection with Helicobacter pylori was identified as an additive risk factor. Risk factors in OTC NSAID users were difficult to identify in the current literature. Risk factors were not all uniformly present in analysed guidelines and consensus agreements. We identified a history of (complicated) peptic ulcer disease, older age, concomitant anticoagulant or corticosteroid use and multiple NSAID use, including low-dose aspirin, as definite gastrointestinal risk factors in NSAID users.