Treatment schedule and survival times in control and sickle mice treated with morphine and saline. (A) Schedule of morphine treatments. (B) Survival of control and sickle mice treated with morphine and saline. Survival was estimated using a Kaplan-Meier curve; the log-rank test was used to compare groups. Control morphine-treated, AA_MS, n = 23; control saline-treated, AA_Saline, n = 21; sickle morphine-treated, SS_MS, n = 22; sickle saline-treated, SS_Saline, n = 20; log-rank test with Sidak correction, *P < .05, ***P < .001 compared with AA_Saline.