International Pharmaceutical Abstracts is one of the most useful databases for pharmacy but is difficult to obtain. Some pharmacists will regularly acquire information by use of one or more bibliographic databases, but many wrongly believe that this facility is only available to specialist librarians. In addition, the National Library of Medicine publishes books of MeSH terms showing how they explode and what is covered under each one. Although all commercial providers of Medline cater for 'natural language' queries to a greater or lesser extent, a more effective search can be carried out by using the MeSH terms that have been selected and combining these with the logical connectors OR and AND. International Pharmaceutical Abstracts is excellent for pharmacy references, but can be even more difficult to source. The issue of unpublished trials is often raised, arguing that negative trials often remain unpublished and that if these could be included they would somehow reverse the answer delivered by the meta-analysis.