Long-term proton pump inhibitor (PPI) prescribing in general practice is common, but only a minority of patients request their prescriptions regularly. This study determined factors linked with compliance using questionnaires and diary cards. The chief factors determining whether or not patients took their PPIs were the presence or severity of symptoms and the desire to remain in personal control, together with a fear of side-effects and lack of knowledge about the drugs. As most such prescribing is for uncomplicated gastro-oesophageal reflux disease, on-demand therapy should now be formally advocated.