Drugs are prescribed for chronic low back pain without knowing in advance whether a patient will respond to them or not. Quantitative sensory tests (QST) can discriminate patients according to sensory phenotype, possibly reflecting underlying mechanisms of pain processing. QST may therefore be a screening tool to identify potential responders to a certain drug. The aim of this study was to investigate whether QST can predict analgesic effects of oxycodone, imipramine and clobazam in chronic low back pain.