The present invention relates to a pharmaceutical composition for use as a medicament in the prophylactic or therapeutic topical treatment of viral eye infections caused by adenovirus of subtype D or influenza A virus of subtype H7. The composition in its ready-for-use formulation comprises iota carrageenan as an active antiviral ingredient and is essentially free of a metal halide salt or contains no more than 0.5% w/v of a metal halide salt.