toy poodle bald spot

Question
the spot is between my 18 month old black toy poodle.  I took him to the vet.  She told me she didn't know shat it was, possibly an infected scratch. I was to put ottomax on it for a week.  What mightit be?

Answer
Hello Sonia,
Without seeing your Poodle, and because I am not a Vet, I can only speculate on what the spot may be caused by.

You didn't say where the spot is, or what it looks like, and that would give me more information to go by.  
If the bald area is scabbed or rough looking, it is most likely a Hot Spot.  Hot Spots can be caused by about anything such as; Flea Bites, Sores that the dog licks and they get infected, skin irritation, allergies, or dry skin that the dog scratches or bites at.  The place will become red and irritated which will make the dog lick or bite at the sore.  The constant licking will cause more irritation which in turn will cause the dog to lick at it more.  
You can apply some antibiotic cream such as Neosporin (I like the kind that also has a Pain Reliever in it).  That will help ease the pain and will take the reddness out of it.  

If you see fleas on your dog, apply a Flea Product (the ones that work need to come from your Vet, such as Frontline or Advantage) according to the package instructions.

If the site of the hairloss isn't scabbed or irritated but just a missing patch of hair, then it could be something such as Medication, Stress, or a reaction to something such as a chemical (dogs can be exposed to things like Household cleaners or yard treatments that you might not even know about)
Be sure that you haven't recently bought a new cleaning product or that the neighbors haven't had their yards sprayed/treated in the last 2 weeks or so.

If you are still unsure about what is causing the missing hair patch, you might want to contact some of the Vets on this site to see if they have any other suggestions.

I hope this helps you some.  If you have other questions, please feel free to ask.
Thanks for using AllExperts.com,
Kim