PURPOSE: To prospectively evaluate tenecteplase (TNK) for thrombolysis in acute lower-limb ischemia. MATERIALS AND METHODS: Forty-three consecutive limbs in 37 patients (15 male, 22 female) were treated for acute lower-limb ischemia. Group 1 included 22 limbs treated with TNK infusion of 0.25 mg/h and group 2 included 21 limbs treated with TNK at 0.125 mg/h. Technical success was defined by 95% clearing of thrombus, and clinical success was defined by Society of Interventional Radiology category for acute ischemia of +1. Complications were ranked by severity and relation to TNK administration. Logistic regression, Student t test, and analysis of variance were performed. RESULTS: TNK infusions averaged 24 hours in duration (SD, 13 h), with means of 20 hours in group 1 and 27 hours in group 2 (P = .071). Technical success was achieved in 84% of limbs (36 of 43): 82% in group 1 (18 of 22) and 86% in group 2 (18 of 21; P = .827). The SIR ischemia category improved (ie, +1) in 86% of limbs (37 of 43), stayed the same (ie, category 0) in 12% of limbs (five of 43), and worsened (ie, -1) in 2% of limbs (one of 43). TNK-related complications were seen in 12% of limbs (n = 5) and were correlated with percentage decrease in fibrinogen level, initial TNK bolus, and abciximab administration (P = .001, P < .001, and P = .036, respectively). Initial TNK boluses of 1.5 mg or less were associated with fewer complications than boluses of 3-5 mg (P = .045). The percentage decrease in fibrinogen level in group 1 was 23% (SD, 29%), compared with 7% in group 2 (SD, 20%; P = .045). There was a 7% incidence of major bleeding complications (n = 3) and no intracranial hemorrhages. CONCLUSIONS: Treatment of acute lower-limb ischemia with TNK infusion at 0.25 mg/h and 0.125 mg/h is associated with similar success and complication rates. TNK-related complications correlated with initial TNK bolus, abciximab treatment, and percent decrease in fibrinogen level. The initial TNK bolus dose should be limited to 1.5 mg.