Pain control using intramuscular analgesia is often unsatisfactory in sickle cell patients. In a pilot study, 15 patients with sickle cell anemia (SS) and one patient with SB thalassemia in vaso-occlusive crisis were treated with the Patient-Controlled Analgesia (PCA) technique using a Pharmacia Deltec Programmable pump (CADD PCA). Age range was 19-50 years (median = 27); there were nine females and seven males. The protocol consisted of 3 days of therapy using a background of continuous infusion meperidine. The starting dose was 20 mg/hr and was escalated to 30 mg/hr. The average amount given was 25.8 mg/hr. One to two boluses of 2.5-5.0 mg/dose (mode = 5.0) were also allowed each hour. In addition, patients number 8 through 16 were given hydroxyzine (Vistaril) 50 mg PO q6h. The number of days in pain prior to study entry (mean +/- SD) was 3.3 +/- 1.6. The number of pain sites per patient was 3.6 +/- 1.2. Using categorical and analog pain scales, patients' pain scores decreased only about 30%. However, most patients were fairly satisfied with the treatment and rated it overall as follows: 1 poor, 1 fair, 3 good, 6 very good, 4 excellent, 1 no comment. Patients number 8 through 16 gave higher ratings probably because a more idealized dosage regimen was being used by that time in the study. There were no adverse effects or major problems noted. It is our impression that PCA, when optimized, will be a safe and effective alternative method for providing patients with sickle cell vaso-occlusive crisis pain relief.