The concurrent use of didanosine and ranitidine results in a minor increase in the
serum levels of didanosine, and a minor decrease in the
serum levels of ranitidine.
Cimetidine raises
serum zalcitabine levels. Cimetidine reduces the
renal secretion of
zidovudine, but does not have a significant effect on zidovudine
serum levels.
None of these changes are expected to be clinically significant.