The present invention provides antiviral peptides having the general structure, Arg-Arg-Trp-Trp-Cys-Arg-X, where X is an amino acid or an amino acid analog, the stereochemistry of the amino acids or amino acid analogs can be (D)- or (L)-amino acids and the amino and carboxy termini of the peptide can be modified. The invention also provides a pharmaceutical composition comprising an antiviral peptide and methods of using an antiviral peptide in vitro or in vivo to reduce or inhibit a herpes simplex virus infection.