Summary: Non-specific immune system stimulation and modulation is the only option available in the case of many infectious diseases, while efficient means of specific prophylaxis, especially vaccines, are not available yet or treatment options are scarce. Among many drugs and dietary supplements marketed today, inosine pranobex and zinc, although both well-known for a long time, present an interesting option when merged into new convenient-to-use fixed pharmaceutical formulations. Since 1971, inosine pranobex has been popular as an antiviral and immune system stimulating agent, while it modulates both cellular and humoral response via direct interactions with lymphocytes and macrophages and via cytokines, increasing chemotaxis and phagocytosis. This translates into positive clinical effects, especially in patients with impaired cellular immune response, as inosine pranobex limits both the number and gravity of recurring upper respiratory tract infections and mitigates influenza symptoms. Inosine pranobex can be used as part of treatment of viral infections or as a means of long-term prophylaxis. Zinc compounds have been well known as effective antibacterial and antiviral agents since ancient times. Although zinc has been proven essential to proper immune system response, zinc deficiency is common, especially among elderly people, and tends to worsen during infections. Administration of inosine pranobex together with zinc as a combination medicine therefore presents an interesting and safe option of immune system stimulation and modulation in a non-specific way, both in children and in adults. Although the results are promising, available means of specific prophylaxis need to be applied whenever possible - including mandatory and recommended vaccinations, especially influenza vaccination.