ZWOLLE, THE NETHERLANDS-- Although penicillin has been the treatment of choice for group A streptococci for four decades, clinicians have grappled for years with concerns about its use and duration. A new study suggests that a seven-day penicillin regimen is far superior to a three-day protocol--and that a drug-free approach is a viable alternative when the risk of rheumatic fever and the need to speed up the recovery process are minimal.[1]

Zwart et al measured the outcomes of 561 patients age 15 to 60 years randomly assigned to a seven-day penicillin regimen, a three-day course followed by four days of placebo, or placebo only. The subjects were selected on the basis of clinical presentation. Each met at least three of four key criteria: history of fever; presence of swollen, tender anterior cervical lymph nodes and/or tonsillar exudate; and absence of cough.

Because recommendations for the duration of penicillin use have varied widely, the researchers set out to determine whether a three-day and seven-day course would be equally effective. They found that patients taking penicillin for seven days fared significantly better on the key outcome measures:

• Symptom resolution: The seven-day group was completely symptom-free almost two days sooner than their counterparts. These subjects also resumed normal activities about two days earlier than those on the three-day regimen or placebo alone.
• Eradication of bacteria: After two weeks, group A streptococci had been eradicated in 72% of patients on the seven-day regimen, 41% of those taking penicillin for three days, and 7% of those on placebo.
• Recurrence rate: After 180 days, sore throat symptoms had returned in 33% of the seven-day group, 38% of the three-day group, and--unexpectedly--only 25% of the placebo group. The reason for the increased rate with the shorter regimen could be that the brief course of therapy reduced the natural immune response and suppressed, but did not eliminate, the pathogen, the authors speculated.

"Prevention of acute rheumatic fever is no longer the main reason to treat patients with penicillin [in Western countries], because of the low incidence of this complication," reported the researchers, headed by Sjoerd Zwart, MD, PhD, of the Julius Center for General Practice and Patient-Oriented Research at the University Medical Center in Utrecht, The Netherlands. "If the aim of penicillin treatment is the acceleration of resolution of symptoms and a reduced risk of suppurative complications, a seven-day course of penicillin is the most effective treatment for adult patients with sore throat caused by group A streptococci and, possibly, those with 3+ non--group A streptococci."

In an interview with RESPIRATORY REVIEWS, Dr. Zwart urged caution in applying the findings. A 10-day course of penicillin, he said, is still recommended for patients with a low standard of living, closed or semiclosed living quarters, recurrent tonsillitis, a history of rheumatic fever, or any other high-risk condition. "For all other patients, a seven-day course for streptococcal pharyngitis will suffice--provided the clinician decides to treat with antibiotics at all. General practitioners in the Netherlands rarely use antibiotics to treat sore throat and only consider penicillin for patients who make a severely ill impression," he noted.

--Helen Lippman

Reference
1. Zwart S, Sachs APE, Ruijs GJHM, et al. Penicillin for acute sore throat: randomised double blind trial of seven days versus three days treatment or placebo in adults. BMJ. 2000;320:150-154.