[Causality relationship of drug adverse reactions: experience in the use of HIV-protease inhibitors]

To establish the exact cause and effect relationship between protease inhibitors (PIs) and adverse events.Prospective, cohort, multicenter study on HIV-positive patients who are beginning treatment with a PI. Causal relationships are evaluated using the RUCAM algorithm.Since the beginning of the study 1207 patients have been enrolled. Average time of observation is 10.7 months. To date, 784 adverse events have been observed, distributed as follows: excluded 3.8%, improbable 18.5%, possible 41.3%, probable 30.1%, and highly probable 6.3%. Saquinavir shows a statistically significant difference in the rate of non-correlated events with respect to other groups.Over 20% of adverse events during PI treatment are shown to be non-correlated to these drugs. Saquinavir shows the highest rate of non-correlated events.