Not only do prolonged courses of antibiotics appear to do no good, the report said, they pose some risk because of possible side effects.

In most cases, patients required prolonged courses of therapy, for several years, to maintain a partial response.

It is also possible, though unlikely, that the prolonged course of treatment was inadequate to eliminate the organism responsible.

A prolonged primary course of study is indicated.

Treatment requires prolonged courses (4-8 weeks) of antibiotics that penetrate the prostate well.

Again, deficiency is rare and occurs only in very ill people, newborn children, or those on prolonged courses of antibiotics.

She said: "This is a terrible area and people are being treated with prolonged courses of antibiotics without any attempt to find out what's going on."

Sinus infections are treated by prolonged courses of antibiotics.

The duration is classically short - one to two weeks, but a prolonged course (two months or more) has been observed.

For those with recurrent infections, a prolonged course of daily antibiotics is effective.