Abstract: The invention provides a method for treating elevated platelet levels in patients using oligonucleotides in formulations that enhance penetration of the oligonucleotide into cells. Certain oligonucleotides found suitable for use in this method are anitisense oligonucleotides. Of the antisense oligonucleotide that are effective, it has been found that antisense oligonucleotides that inhibit the expression of the raf-1 gene can be used, for example, formulated in liposomes. The method has the advantage that the formulation of oligonucleotide can be administered to human patients and the platelet count will decrease in the absence of additional therapeutic treatment steps, including other chemotherapeutic or radiation treatments.