Background Blood injection injury (BII) phobia is common, with debilitating consequences to the health and well being of many of its sufferers. BII phobia presents with a unique fear response that can involve drops in blood pressure and ultimately fainting. The aim of this study was to provide proof of concept for a line of brief, easy to implement, video‐based interventions for reducing phobic avoidance and fears in BII sufferers. One of the interventions was a novel Hypoventilation Respiratory Training (HRT) aimed at reducing the exaggerated ventilation response (hyperventilation) seen in BII phobia. The response has been linked to cerebral vasoconstriction and fainting symptoms. Method Sixty BII patients were randomly assigned to one of three 12‐min video‐guided trainings: Symptom‐Associated Tension (SAT) training, Relaxation Skills Training (RST), or HRT. Experiential and cardiorespiratory activity to phobic stimuli was assessed before and after training. Results Both SAT and HRT resulted in overall greater reductions of phobic fears and symptoms than RST. SAT significantly increased heart rate during exposure, and HRT led to significantly reduced ventilation, increases in PCO2, and elevated blood pressure throughout exposure and recovery. Treatment expectancy was rated equally high across conditions, whereas credibility ratings were highest for HRT. Conclusions Brief, video‐based instructions in muscle tension and normocapnic breathing are effective in reducing BII symptom severity and require minimal time and expertise. HRT may be particularly helpful in reducing fainting caused by cerebral vasoconstriction.