Dalmatian with skin problem

Question
I have a 11 year old dalmatian and about 16 months ago he has a lesion on his back right leg between ankle and his toe. Our Vet did a blood test that came back fine.  Put his on antibotics I think 3 times.  He also got another on the left foot beside little toe.   He has been wearing a cone for 8+ months now to keep him from licking them.
He also is on Rimadyl & Amitriptyline (he is very nervous).  Will about 2 weeks ago he got these on all legs, inner/outer thighs, between toes, a few on his sides..  They open up some and bleed and then scab over.  Some reopen..  He also has a smell to him..
His nose recently has become crusty, alittle swellin in the holes of his nose and dry on the edges..  I was thinking it maybe the Rimadyl.
He also drinks alot of water.  Which he always has.  But now seems alittle more..  Could it be the medication?
I took him back to the Vet last week again
I also got him to do Skin Scraping they were negative other then in the Drain Tract there was Bacterial & Yeast.  So, he is also on Cepahlexin & Ketoconzole.. He looked at his nose and didn't say anything.  I feel our Vet has giving up..
Our Vet in the beginning thought it would clear up but, now has no idea what is going on..  And didn't really want to run test on him..
The nearest Dermatologist is hours away..  
He has been on the medications for the Bacterial & yeast for 6 days and they look alittle better I am not having to wash bedding everyday now..Funds are getting tight So,
Any ideas or help would appreciated..  
Thanks Renee'  

Answer
When there is bacteria and yeast on the skin, that is very suggestive of allergic skin disease. If your vet has not used any corticosteroids yet, that might be the next step.  Also a skin biopsy may be needed to see if there are mange mites or fungal lesions deep in the skin.