In dogs undergoing hemilaminectomy for acute intervertebral disc extrusion (IVDE), adjunctive nonpharmacologic therapies may help provide postoperative analgesia while reducing reliance on opioids and their associated adverse effects. This prospective, randomized, blinded, controlled trial evaluated the short-term analgesic effects of interferential current electrotherapy (IFC) in dogs following thoracolumbar hemilaminectomy for acute IVDE. Twenty dogs were randomly assigned to receive conventional analgesia alone (control, n = 10) or conventional analgesia plus IFC (n = 10). The IFC group received three IFC sessions administered within the first 24 h postoperatively. Outcome measures were collected at three predefined postoperative time points corresponding to IFC treatment sessions: T1 (2–4 h), T2 (8–18 h), and T3 (20–24 h postoperatively). Outcome measures included Modified Glasgow Composite Pain Scale–Short Form (CMPS-SF) scores, total postoperative opioid consumption, and peri-incisional mechanical sensory thresholds. Dogs treated with IFC demonstrated significantly lower CMPS-SF pain scores at the T2 time point compared with controls (p = 0.03); however, no differences were observed at T1 or T3 time points. Total opioid consumption and mechanical sensory thresholds did not differ significantly between groups at any time point. These findings suggest that IFC may provide transient postoperative analgesic benefit but does not appear to reduce opioid requirements or mechanical sensory thresholds within the first 24 h following hemilaminectomy. Further studies with larger sample sizes are warranted to better define the role of IFC in multimodal postoperative pain management and to explore optimal treatment protocols.