Anaemia has been seen in kidney transplant patients given
azathioprine with enalapril
or
captopril. Leucopenia occasionally occurs when
captopril is given with azathiopr-
ine.
Azathioprine is rapidly and extensively metabolised to mercaptopurine. Mercaptopurine is therefore expected to share the interactions of
azathioprine.
The manufacturer of
captopril recommends that it should be used with extreme caution in patients taking immunosuppressants, especially if there is
renal impairment. They advise that differential white blood cell counts should be performed before therapy, then every 2 weeks in the first 3 months of
captopril use, and periodically thereafter. Any effect seems likely to be a group interaction, and it would therefore seem prudent to consider monitoring with any ACE inhibitor.