Anxiety and phobia frequently prevent patients with multiple sclerosis (MS) from self-injecting their injectable disease-modifying medications. This small, randomized, controlled trial tested the efficacy of a six-session nurse-administered programme to teach self-injection to patients with MS, who, due to anxiety or phobia, were unable to self-inject their injectable medications. Participants were 30 patients with MS who were prescribed interferon beta-1a (IFNβ-1a) administered via weekly intramuscular injection. All patients were unable to self-inject due to anxiety or phobia. Patients were randomized to either the six-session Self-Injection Anxiety Therapy (SIAT) or a control telephone support condition modelled on the support programme offered by the manufacturer of IFNβ-1a. Four patients dropped out of SIATwhile three dropped out of the control condition. Eight patients receiving SIAT, compared to three control patients, were able to self-inject after six weeks of treatment. SIAT patients were significantly more likely to achieve self-injection at treatment cessation, compared to telephone control patients, in completer analyses (p=0.022), however, this only reached a trend in intent-to-treat analyses (p=0.058). These findings suggest that SIAT is a potentially valuable intervention to teach self-injection skills to injection phobic and anxious patients, and should be investigated more thoroughly in a larger clinical trial.