Winnicott's concept of transitional phenomena is employed as a means of further understanding the effect of medicine and the medication-giving process itself. Particular facets examined include the "soothing" function of medication, the placebo effect, and medication compliance, as well as countertransference difficulties encountered in administering the medicine. Medication as a transitional object is viewed largely as a creation along the self-object interface, with the "potential space" between patient and therapist recapitulating aspects of the original dyad. This usage of medicine as a transitional object, or its ultimate abandonment as such, is presented in terms of the vicissitudes of internal object relations, with clinical case examples to clarify particular issues.