There's good news and bad news for balding Americans.

The good news: A new drug, Minoxidil, offers real hope.

The bad news: 1) under the best possible circumstances it's unlikely to work on everyone, 2) it probably will not be on the market before 1985-86 and 3) when it does become available, it is likely to be expensive.

"Unquestionably," says Dr. Thomas Nigra, "there is promise in that it works. The question still is 'How often does it work, and who will really get a good result?' We're seeing successful hair regrowth."

Nigra, chairman of the department of dermatology at Washington Hospital Center, is directing one of several Minoxidil studies involving around 2,000 people nationwide. There are 96 people in his program and, he stresses, no new applications are being considered.

When Nigra posted a call for volunteers, "All of the trunk lines--40 lines coming into the institution--were blocked for two to three days. Even emergency calls couldn't get through." In addition, his office received 4,000-5,000 written inquiries. That was five months ago. "Now, we still get three or four calls a day on a special line."

Minoxidil's hair-growing properties were discovered when it was being tested by the Upjohn pharmaceutical company as an oral medication for hypertension. The current studies are to test its safety and determine if there are any side effects from its use as a topical lotion.

"A decision has already been made by Upjohn to manufacture the drug," says Nigra. "We're doing the study, but they already know it works. We know it works. They wouldn't be spending all this money if they didn't feel they had something successful.

"I think we're going to end up saying that almost anybody that's bald probably deserves a trial of this before they give up. That's a little bit premature, but that's my impression."