Imiquimod
"HPV base of penis about 15+ yrs ago. 7 to 8 warts ranging in size from small dot like this "." to 2 to 3 mm further out from base. 1st had liquid N2 applied.. came back w/in 6 months.

Prescribed Aldara (new on market at the time & I don't think the side effects were well or widely known?)

I was told small amount once /day, 14 days.  

By the evening of the 2nd day fever-
chills started. Application site was irritated. Day 5 was  AGONY. Felt as if skin, including scrotum had been peeled off! (didnt put it there). Fever, achy (immune response in high gear!)

Stopped treatment, pain continued to worsen 2 days.  2 weeks to heal....BUT HPV COMPLETELY GONE 15+ yrs.

 I would recommend stop @ 1st sign of irritation, wait, apply again, stop, etc"