How often do you wash his bowl?  Bowl gets greasy, chin gets greasy, chin
breaks out.

Wash the bowls frequently, keep his chin clean and if it doesn't clear up
you can use benzoil peroxide (2%) available at the drug store in with the
acne medications. Read the labels though

W

My vet recommends cleaning the affected acne area with something like
phisoderm (sp?).

Sue

Here's a tip -  if you're worried take him to the vet for a proper
diagnosis. No one in this ng is qualified to tell you anything more.

Depends on what the lesion is.  It could be Eosiniphilic Granuloma
complex (EGC), it could be kitty acne, although kitty acne usually
presents as a group of blocked pores - like black heads, it could be a
cyst, or it could be a wound from playing.  If it reoccurs in the same
place, it is most likely ECG or a cyst.  See a vet if it bothers the
cat.  You can always clean it with a mild, unscented soap (like
Phisoderm, which someone else mentioned) and clean it *once* with
peroxide, to see if that helps dry up the wound.  DO NOT use peroxide
repeatedly as it kills new tissue.  Alternately you can use the
"no-sting" antiseptic from Bactine which contains benzalkonium
chloride, or use just a plain sterile saline wash (like sterile saline
for opthalmic use, with no preservatives).  If it doesn't look better
after cleaning in a couple days, then see a vet.

-L.

My Maine Coon has the same thing.  One big zit in the middle of his
lower lip popped up last week.  I have tried hydrogen peroxide and that
didn't make it better.  He has no plastic dishes and I wash the ones he
uses at least once a day.  He has had smaller ones in the past, but
usually two or three at a time, not just one.  He doesn't go outside
and is the only pet.  He has a vet appointment this afternoon.  Wish I
knew how to prevent this stuff!

My one cat as he got older got sloppier as he ate.  I just washed his chin
off for him on a daily basis and it eliminated the problem.  Once you have
it healed just a quick wash with a wet paper towel should do it.

Celeste

My Tucker seems to get cat acne once or twice per year for no apparent
reason. (Bowls are washed twice per day, no plastic, etc.) If you have
stainless steel bowls, try using ceramic. The steel seemed to make it
worse.

I tried every treatment I'd ever heard/read about and nothing
helped--and then my vet prescribed something called Pyobin (sp?). It's
a benzyol peroxide type of cream you apply to their chin once per day,
slowly backing off as it clears up. It works great and only cost about
$10.