The concentration of
josamycin was determined in the split ejaculate of 5 volunteers after
oral administration for several days. One aim of this investigation was to examine the penetration of the
macrolide antibiotic into the prostate and the seminal vesicles. 2.23 +/- 1.8 micrograms/ml
josamycin was found in fraction I of the ejaculate, consisting mostly of prostatic secretion, and 1.56 +/- 1.37 micrograms/ml
josamycin in fraction II comprising mainly secretions from the seminal vesicles. The concentrations of
josamycin found in both fractions of the ejaculate are clearly comparable with serum levels of the
antibiotic.
Josamycin thus attains concentrations in the prostate and seminal vesicles which are effective against Mycoplasma and Chlamydia, pathogens of increasing importance in
infections of the urogenital tract. In vitro studies on samples from 30 andrological patients showed that
josamycin (0.5 micrograms/ml) did not impair, but even increased the motility of spermatozoa (p less than or equal to 0.01). On the basis of these results
josamycin is recommended for the treatment of andrological patients. In particular, the specific antibacterial spectrum also indicates the use of this
antibiotic for treatment of the partner when children are desired. The usual precautionary measures for pregnancy must then be adhered to.