Every year, 300,000 Americans with appendicitis are rushed into emergency surgery. Most are told that if the appendix is not immediately removed, it will burst — with potentially fatal consequences.

But now some doctors say there may another option: antibiotics.

Five small studies from Europe, involving a total of 1,000 patients, indicate that antibiotics can cure some patients with appendicitis; about 70 percent of those who took the pills did not require surgery. Those who wound up having an appendectomy after trying antibiotics first did not face any more complications that those who had surgery immediately.

"These studies seem to indicate that antibiotics can cure appendicitis in many patients," said Dr. David Talan, a specialist in emergency medicine and infectious diseases at the University of California, Los Angeles. "You at least have the chance of avoiding surgery altogether."

Talan and other researchers are planning a large clinical trial to compare people with appendicitis who receive antibiotics or surgery. By suggesting an antibiotic alternative, the researchers are bucking long-standing medical tradition.

Surgical treatment for appendicitis began in the 1880s, when surgery itself was something of a new idea. Doctors struggled to figure out which patients to operate on, because the procedure was dangerous and they knew some patients would get better without it.

As surgery and anesthesia improved, however, the appendectomy became the treatment of choice. According to the medical thinking of the day, it made sense.

For years, doctors thought the appendix — a tiny worm-shaped tube that hangs off the right side of the colon — became inflamed because it was blocked by a small piece of hardened feces. As it turns out, though, the vast majority of people with appendicitis do not have such a blockage.

"No one knows what causes appendicitis," said Dr. James Barone, a retired chairman of surgery at Stamford Hospital in Connecticut and Lincoln Hospital in the Bronx.

And an inflamed appendix is not, as most people think, a ticking time bomb. While perforation occurs in 15 to 25 percent of patients, researchers hypothesize that those who get perforations may have a predisposing immune response or infection with certain kinds of bacteria. In others, appendicitis goes away on its own.

But surprising as antibiotics might seem, this is not the first time they have emerged as a possible alternative to an appendectomy.

When antibiotics became available in the 1940s and '50s, doctors in England began giving them to patients with appendicitis, reporting excellent results. During the Cold War, when American sailors spent six months or more on nuclear submarines prohibited from surfacing, those who developed appendicitis were given antibiotics.

"Those submariners did great, and no deaths or complications were reported," said Dr. David Flum, a surgeon at the University of Washington.

But that did not put a dent in the perception that surgery was the treatment of choice. In 1961, a Russian doctor stationed in Antarctica, Leonid Rogozov, went so far as to cut out his own appendix when it became inflamed. "I work mainly by touch. The bleeding is quite heavy, but I take my time," he wrote in his journal.

The planned clinical trial pitting antibiotics against surgery will attempt to answer important questions. Are antibiotics as good as surgery in curing appendicitis? Could they do so at less cost, avoiding a hospitalization afterward? How often does appendicitis recur after a person is treated with antibiotics? Will patients successfully treated with antibiotics later rush to the emergency room every time they feel abdominal pain?

It's not even clear how the drugs should be administered.

In the European trials, patients had a day or two of intravenous infusions at a hospital, then went home to take a week of pills. But, Talan said, there are now long-acting intravenous antibiotics that may permit some patients to simply visit a doctor for a couple of days, and then take pills — while avoiding hospitalization.

There is already a debate over whether to tell patients about the antibiotic option, and if so, which patients to tell.

Dr. Giana Davidson, a general surgeon at the University of Washington, will discuss antibiotics with patients who ask, but has qualms about drugs as a treatment option.

"We don't have the answers to questions that matter to patients," Davidson said. "What are the chances of it coming back? When I get belly pain, what should make me come back to the hospital?"

"I just have a lot of hesitation on my side to go away from a 30-minute operation that cures them for the rest of their lives," she added.