I have allergies... And my eyes will get so itchy and red at times. How can I prevent this?

Allergy eye drops. Drops are still the best treatment for allergy eyes. Otc drops like alaway, zaditor, (ketotifen) and zyrtec are very effective. Be careful, though. Many drops that claim to "get the red out" contain naphazoline- a compound which shrinks the blood vessels. Over use of napazoline containing drops can lead to a "rebound" effect where the redness gets worse when the drops wear off.
Eye drops. For itchy eyes, prescription Patanol (olopatadine) can help regular use of your allergy medications such as over the counter anti histamines, singular if required.