Bruising / Blister on Penis Head after Sexual Intercourse

For the past 5 or more years, I had been experiencing some tearing and bleeding of the penis skin where it meets the bottom of the head of the penis (where I had been circumcized). Typically this occurs during vaginal sex from behind (there was some friction or contact). Sex from behind was easier (less vaginal dryness) and better penetration as we got older. I began using a condom which helped to some extent (but not completely).
  About 18 months ago the head of the penis started to develop one large blood blister about the size of the end of my thumb from the last joint to the tip of the thumb. This would not break but would subside within a day or two. This would always be on the right of the penis, nearest where the skin was most likely to tear. At first, it didn't occur everytime, particularly with good lubrication. Now it occurs everytime I have sex (even if I wait a month or more between episodes). The head of the penis started to swell a little at the back edge and to appear almost bruised (purply colour as opposed to red). The last time I had sex (about one month ago), a similar blister started to appear on the left side. They were gone within 2 days. Most of the symptions are gone now, but the head still remains sensitive to the touch. I tried rubbing the affected areas at the tip of the penis during masturbation about 2 weeks ago (as an experiment as much as anything) and the area was tender. I believe I could have brought back the blister if I had continued the friction on this spot during masturbation.
  I visited a doctor last week. I had a different partner approximately 3 and 1/2 years ago (used a condom). The doctor wants to test me for herpes. From what I can read I have not had typical symptons of herpes.

[Alan Rockoff, MD]

This sounds like a friction blister, not herpes.  I'm not sure what test the doctor wants to do.  I suppose culturing a blister when it's fresh is easy enough, but it's not likely to be useful.

It seems to me that your own analysis is correct, and that you should do best by minimizing friction any way you can,  as you have been doing.  Lubrication is the key.

If you can't prevent these blisters by lubrication, you should show them to a dermatologist or urologist when they're fresh (or photograph them).

Best.

Dr. Rockoff

[juliuscaesario]

A related discussion, Long Blisters on penis head was started.