Transdermal delivery of drugs is a novel method of pharmacotherapy for many diseases. The main advantages of this method of administration are

• prolongation of the drug action;
• absence of the drug concentration hopping;
• decrease of the side effect risk.

This method of administration has to be viewed for preventive actions and therapy of viral respiratory infections. The aim of this work was studying the possibility of transdermal rimantadine delivery for influenza A prophylaxis and treatment in experimental animals. Rimantadine was administrated in the hydrogel matrix (formed from 1.2-propylene glycol and polyvinyl alcohol) in the doses 1 or 2 mg/mouse applied on the shaved back of mice 1 day before infection. Mice of experimental and control groups were infected intranasally with highly pathogenic influenza virus A/PR/8/34 (H1N1). Challenge was carried out using 4 animals for each virus dilution within the range of 10-1 to 10-7. Deaths of animals were recorded for 14 days. The results of our investigations had shown high anti-influenza efficacy of rimantadine under transdermal delivery. Differences of LD50 between control and experimental groups consist 1.7-1.75 log10 when dose of rimantadine was 1 mg/mouse and 2.25 log10 when preparation was administrated in dose 2mg/mouse. In this study the anti-influenza efficacy of rimantadine after its transdermal administration was established for the first time.