Upjohn Co. says it plans to promote Rogaine, its new $600-a-year prescription hair growth medication, with a television advertising campaign backed by a budget that could reach $20 million.

The company, which said Thursday it has shipped the drug to pharmacies nationwide, also said it filed federal lawsuits against two Nevada pharmaceutical firms, alleging those companies' products do not stimulate hair growth or arrest hair loss as stated in their advertisements.The Kalamazoo, Mich., company held a Manhattan news conference to announce that minoxidil-based Rogaine Topical Solution, approved in August by the Food and Drug Administration, now is available to balding men nationwide.

Daily topical application of dilute minoxidil - initially studied as a hypertension drug - has been shown to cause significant hair growth on the heads of 39 percent of the balding men who participated in Upjohn studies. There was no effect on about 15 percent, and the remainder showed marginal results.

The FDA approval extends only to men, but Upjohn is testing minoxidil's effects on women.

Upjohn President Lawrence Hoff said the FDA has approved a television commercial that mentions Upjohn but not the product's name.

"The ad says, `There is a hair-growth product, it works, please see your doctor,"' Hoff said.

Upjohn may spend as much as $20 million to broadcast the commercial.

Upjohn is charging pharmacists $42.50 for a 60-milliliter bottle of Rogaine, a one-month's supply, and the drug is being promoted by national chains at prices ranging from $43 to $50 a bottle - about $600 a year, Hoff said.

Tests show Rogaine is more effective in younger men than older men and its twice-daily use must be continued indefinitely, with the effects beginning to show between the fourth and eighth month of treatment.