Tagamet (Cimetidine) is sometimes recommended for the treatment of warts or verrucae. It is normally used to treat gastrointestinal conditions, but anecdotes have suggested that it may have an affect on the warts or verrucae. The clinical trials have not really supported what has been anecdotally reported.
It is thought that if Tagamet (Cimetidine) was to help, then the mechanism is most likely to be via triggering an immune reaction that is effective at resolving the verrucae. Mitsuishi et al (2003) in their study showed that the IL‐2 and IFN‐γ mRNA levels were significantly increased and IL‐18 mRNA levels were decreased in tissues of those who were treated with cimetidine successfully in their uncontrolled study. This supports the possible immune mediated action of Tagamet.