Skin Irritations Flaring Up

Ziggy's skin condition has escalated in the past week or two.  He licks and bites on his legs and feet a lot.  The bleeding spot on his foot has returned (indication of the cysts).   The skin seems to clear up and do well for a couple of weeks, then it worsens.  He smells very yeasty.  I bathe him with the Douxo shampoo and that seems to help a little but it's only temporary.

His ears seem to be doing ok.  I clean them every day or two and apply the Mometamax.  Not sure if that is keeping his ears clean or if it's the homeopathic remedies.  He's been on the latest round of remedies for about 3 weeks or so.

He's usually very lethargic but has occasional bursts of energy (usually after eating or coming in from his walk).  I'm wondering if I should add a multi-vitamin to his diet.  Current diet is turkey and vegetables (peas, corn, carrots, green beans organic frozen veggie mix) and the powdered bone meal supplement.  He also drinks a little organic whole milk after his meals.  Could the milk be causing some of the skin issues?  His snacks consist of greenies and the Bravo dry-roasted chicken breast strips.

Here are some pictures I took this morning:

Back left leg. 

Very red and raw from licking and chewing.

Inside of back legs.  It's actually redder than this picture shows.

His foot bled yesterday so I bandaged it up overnight and so the blood has dried. 

He's licking at it right now as I type.