Ton of information for you. We need to go back all the way to the beginning.
Yes, grass allergies are quite common. But, he very well could be allergic to far more environmental things unless you already had him blood tested for allergy issues. There are also food allergies, although they only account for about 1 in 4 allergic dogs.
Bathing every day is a lot! It's really worthless though if you are not using a strong medicated shampoo from your vet. In addition, it strongly sounds like there is a secondary infection, so it would be greatly helpful to get him started on oral antibiotics and possible oral antiyeast medication.
Well, the secondary infection is the primary problem first. Not the allergy. Infection, in itself, makes allergy symptoms worse!!!
So, jumping to cyclosporine, is useless if infection is not treated.
Now, the really expensive cyclosporine is known as Atopica. Yes, that is a popular medication for long-term treatment of bad allergy problems.
Another newer drug is called Apoquel. Wonderful as well but very costly and hard to get still due to backordering.
Your fastest and least expensive medication to help with allergies is going to be prednisone. Yes, a good steroid! But, you must get from your vet. No choice.
The skin is darkening due to hyperpigmentation. This is common with chronic allergies, and is often caused by chronic irritaiton, usually excessive licking, chewing or scratching of the skin.
So, my suggestion:
1. New vet check up
2. Request oral prendisone
3. Get stated on a good oral antibiotic and possibly antiyeast as well. A simple skin cytology can determine what type of infection is present.
4. Get a STRONG medicated shampoo. Something with chlorhexidene and a antiyeast product. Stuff at the pet store is not good enough!
Hope that new information helps