Because headache is a common side effect of electroconvulsive therapy (ECT), this study sought to determine the effectiveness of cryotherapy (i.e., a frozen gel band) in relieving pain in patients with post-ECT headaches, and whether headache intensity and physiological measurements could predict use of an alternative analgesic (rescue medication). We used a quasi-experimental, crossover design to collect data from 31 patients ages 24 to 85 who had been referred for ECT at two medical facilities in San Diego, California. Measurements of patients' pain intensity were made at three intervals: upon perceiving headache, and at 30 and 60 minutes following the cryotherapy or acetaminophen interventions, based on the order of the crossover design. Data were analyzed using Hotelling's T2 and logistic regression. No significant difference was found between cryotherapy and acetaminophen in relieving ECT-induced headaches (p = .420). There was no influence due to the crossover design (p = .313), nor where there significant changes in physiological measures from treatment (p = .420). Logistic regression showed that 50% of patients required rescue medication after 60 minutes for both treatments (R2 = .498, p = .001), and 66% required rescue medication based on pain level and physiological measures (R2 = .662, p < .008). Based on these results, cryotherapy is an alternative treatment that may be helpful to some patients with ECT-induced headaches.