Background - This non-interventional study was performed to generate data on safety and treatment effects of a complex homeopathic drug (Contramutan N Saft).Patients and methods - 1050 outpatients suffering from common cold were treated with the medication for 8 days. The study was conducted in 64 outpatient practices of medical doctors trained in CAM. Tolerability, compliance and the treatment effects were assessed by the physicians and by patient diaries. Adverse events were collected and assessed with specific attention to homeopathic aggravation and proving symptoms. Each adverse effect was additionally evaluated by an advisory board of experts.Results - The physicians detected 60 adverse events from 46 patients (4.4%). Adverse drug reactions occurred in 14 patients (1.3%). Six patients showed proving symptoms (0.57%) and only one homeopathic aggravation (0.1%) appeared. The rate of compliance was 84% in average for all groups and the global assessment of the treatment effects attributed to “goodâ€? and “very goodâ€? in 84.9% of all patients.Conclusions - The homeopathic complex drug was shown to be safe and effective for children and adults likewise. Adverse reactions specifically related to homeopathic principles are very rare. All observed events recovered quickly and were of mild to moderate intensity.