My puppy has a skin rash after grass. Is it allergies? What can I use?

It sounds as if your dog has a skin infection, most commonly caused by an allergy, a skin mite (Demodex) or fleas. 

The allergy could be a due to a protein in your dog’s food or an environmental allergy like to dust, pollens, grasses, etc. 

The allergy causes your dog to itch and chew at the skin which breaks down the skin barrier. This then leads to infection. Skin infections are typically characterized by large areas of hair loss, redness, crusting, flaking, and pustules.

A thorough skin examination by your veterinarian should be able to determine the cause of the itch so it can be treated appropriately.

Your dog will most likely need antibiotics to help clear up the infection and possibly an allergy/anti-itch medication like Apoquel, Atopica, or Cytopoint to give some relief while the infection clears up. A medicated shampoo may be beneficial as well. I would also recommend he be on a good flea control routinely too. Once the infection has resolved a long term allergy medication (like Apoquel or Cytopoint) can be given on a regular basis to prevent any future problems.

I would avoid putting anything on the skin until the infection is under control.

I hope this helps. Thanks for using Petco Pet Education Center, formerly Petcoach. Best of luck.