First, there's the itching and burning.

Patients who suffer from Herpes labialis, commonly called cold sores, recognize these initial symptoms days before a blister ever emerges.

Then, the outbreak, usually along the edge of the lip, oozes, crusts over and eventually, up to two weeks later, heals.

There are topical and oral treatments, both over-the-counter and prescription, but there is no cure and many of the most widely available creams and pills must be applied or swallowed five times a day for several days. They only speed "time to healing" by about 12 hours.

"It's hard to remember to take a pill five times a day," said Dr. John Maize, Jr., a Charleston dermatologist.

That's what makes Sitavig, a brand-new FDA-approved prescription, seem different, he said. The drug was developed by BioAlliance Pharma and introduced to the market in July by Innocutis, a Charleston-based pharmaceutical company.

Sitavig administers a low dose of acyclovir, basically the same active ingredient found in most cold sore treatments. But instead of a pill or a cream, Sitavig is a tasteless tablet that's placed underneath the upper lip. It dissolves slowly over 12 hours and it's only applied one time over the life of the cold sore.

"It's a novel way of administering the medicine," Maize said. "It's the same drug. It's just a different delivery system."

Clinical studies determined it only speeds time to healing by about 12 hours, but many patients who applied the tablet at the first signs of a cold sore never even reached the blister stage. It also reduced the number of cold sores patients developed over the course of a year.

"We've heard things like, 'This is a game-changer,'" said Chuck Jenkins, vice president for marketing at Innocutis. He did not know how often Sitavig has been prescribed across the country since its July launch.

"Early indications and early feedback has been phenomenal, but we don't see actual prescription data for about another month or so."

Two Sitavig tablets, which are available only through a doctor's prescription, cost about $300, but the company said most insured patients will only pay about $35 through co-payments and the Innocutis rebate program. That makes the cost of Sitavig comparable to some of the over-the-counter creams available at many pharmacies. Abreva, for example, retails at Walgreens for about $21.

"Whatever their insurance does not pick up, we come in and offset it," Jenkins said. "It's a massive market."

The Mayo Clinic estimates 90 percent of adults test positive for the virus that causes cold sores, although many of them never show symptoms.

"Patients often acquire this (virus) in childhood, although it's possible to acquire it as a virus at anytime," Maize said.

The virus lives in the nerves and outbreaks typically occur during times of stress.

"People are very excited about it because they want to have something they can do when they first get an outbreak," said Dr. Todd Schlesinger, a local dermatologist and a paid consultant for Innocutis. "When you first start getting the symptoms of the outbreak, that's when you want to treat."

Schlesinger has prescribed the drug and has heard from patients that Sitavig is easy to use. Maize has not prescribed it yet, but said he would consider the tablet among other options. Some patients decline treatment altogether, he acknowledged.

"Sometimes reassurance is all that they want," he said.

Reach Lauren Sausser at 937-5598.