The medications you are currently using are, on average, about 25% effective, so 60% sounds a lot better to me!
The over the counter medications are only effective for MILD allergies, and as a preventative early in the season. It also takes trial and error to find a medication that will work for your pet, because there is a lot of individual variability in the drug response. You are wasting your money if the drugs aren't helping. You also need to control secondary infections and the inflammation, and antihistamines do nothing for this.
Allergy shots do help, they are not likely to cure the allergies, are expensive, and require a lot of commitment on your part. Allergy shots are the ONLY treatment that treats the actual disease rather than the symptoms, and even if its not a cure, its still an excellent treatment.