A computerized Medication Awareness Reporting System (MARS) generated by a Sperry PC microcomputer with an Epson FX-80+ printer was evaluated on four adult units (163 beds) of a 353-bed community hospital. MARS is a drug database containing clinical information monographs on 200 commonly prescribed medications. Information provided through the MARS system includes mechanism of action, dosage and administration guidelines, adverse effects and contraindications. In addition, pharmacists can add written information to each MARS report. Patient-specific MARS reports were generated on all patients admitted to the four units during the 16-week study period. Copies of the reports were placed into each patient's chart and into the patient's medication Kardex. Reports were updated daily by pharmacists who provide decentralized service to the units. Physicians, pharmacists, and nurses who encountered the MARS reports were surveyed at the end of the 16-week period. The results indicated that nurses used MARS more than physicians or pharmacists. The groups that valued the MARS reports as a source of drug information the least were the pharmacists and the physicians. MARS, or a drug information system similar to MARS, can be provided with relatively little cost for equipment and materials. However, the use of MARS as described in this study may be limited due to the time required to provide this service. More efficient methods of delivering MARS may enhance its use in the hospital setting. Currently, MARS may be more appropriate for use in long-term care facilities and home health agencies.