What Causes Itching In Sexual Organ?

Hello: Recently,am suffering in pneumonia. My doctor suggested placentrex injection. after using 5 days, i got itching in my sexual organ. i want to know is it because of this drug or am having any other problem? My mom said if in case i have diabetic also it will itch like this. My age is 27 and also am bit over weight. My parents have history of diabetes. Am working in IT industry