You're all too familiar with the discomfort that comes with an allergy attack all too well: the runny nose, red eyes, itchy throat and dry cough. These classic symptoms can prompt you to rush to your nearest drug store in search of relief, but the vast array of medications on the market today may be confusing enough to make your head swim.

To better understand the choices that exist, we've outlined some of the most popular categories of allergy medications, along with a brief description of their benefits and side effects.

Antihistamines

Antihistamines work by blocking a chemical released by your body during an allergy attack that can cause a host of unpleasant symptoms. This medication comes in oral and nasal form and is available both over the counter and by prescription.

  • Oral antihistamines are taken by mouth and absorbed into the bloodstream. They come in several forms (including tablets, capsules and liquids), and serve as a brief intervention, with repeated doses needed to maintain the effects. Some of the older types of oral antihistamines, like Benadryl®, also cause mild to severe drowsiness. Some of the newer oral antihistamines, such as Claritin®, Zyrtec® and Allegra®, among many others, are longer acting and are less likely to make you tired.

  • Nasal Antihistamines work by delivering a fine mist of medication directly into the nasal cavity. This allows it to take effect quickly. Some nasal antihistamines also treat allergy eye symptoms. There are some minor possible side effects with nasal antihistamines, which include headaches, sedation and a bitter taste upon use. Two nasal antihistamines you can find on the market today are Astelin and Patanase®.

  • Antihistamine Eye Drops reduce swelling in your eyes and can help treat the redness, itch and irritation occurs with an allergy. The benefits only last for a few hours, though, before needing to be repeated. Side effects are generally mild but can include burning, stinging and irritation of the eye area. Common types of antihistamine eye drops include Visine-A® and Opcon-A® (these two are available without a prescription), as well as prescription options such as Naphazoline, Emadine and Patanol®.

Corticosteroids

Corticosteroids, also known as steroids, work to reduce inflammation and offer more intensive relief for those allergy suffers who need a serious treatment strategy to help manage their symptoms. Available by a doctor's prescription only, such steroids are available in both oral and nasal form and are often very effective.

  • Oral Steroids are generally prescribed for people experiencing ongoing asthma symptoms or other lung issues. This medication comes in tablets and liquid and works very quickly. The downside, though, is that the medication affects your entire system and results in a host of side effects, including increased appetite and weight gain. Therefore, oral steroids, which include Prednisone and Methylprednisolone, are usually used only as a short-term strategy. Once your condition is under control, your doctor will likely recommend a more moderate strategy.

  • Nasal Corticosteroids are nose sprays that deliver a natural steroid into your nose to reduce inflammation in the lining and open the passages for more comfortable breathing. This medication, which is generally approved for longer-term use, is often a treatment method of choice for hay fever and pet allergies. The risk of side effects is also greatly reduced when you take steroids in nasal, rather than oral, form. Many new formulations of nasal corticosteroids have come on the market lately. Some popular choices include Nasonex®, Flonase®, Pulmicort®, along with a new medication called Veramyst®, which treats a variety of nasal and eye symptoms with one easy-to-use spray mist.

  • Corticosteroid Eye Drops are available by prescription only and are generally used only when allergy eye symptoms are severe. They work by reducing redness, itching and irritation. Side effects can occur with prolonged use and include blurred vision and increased risk of infection. This class of medication includes Decadron, Fluor-Op and Econopred. These are generally not recommended for use by pregnant women.

Decongestants

Decongestants work to clear your stuffy nose and head. This medication is a stimulant that shrinks the swollen blood vessels in your nose, allowing it to drain. While it doesn't treat the sneezing and itchy eyes and nose, it can lessen some of the stuffiness and discomfort caused by allergies and also by cold symptoms. It is important to note that the FDA recently banned the use of phenylpropanolamine in decongestants, as it can lead to serious side effects. The decongestants for sale today are considered safe now by FDA standards.

  • Oral Decongestants come both in pill and liquid form, and can also found in some oral antihistamines. Unlike antihistamines, though, which can cause drowsiness, decongestants can be a stimulant. As a result, some patients find it causes over excitability and an inability to sleep. Other possible side effects to consider include nervousness, increased heart rate and an irregular heart beat. Despite the risks that exist, there are many decongestants on the market today, including Sudafed®, Triaminic®, Poly-Histine and Dura-Vent. However, patients with high blood pressure and other risk factors should steer clear of these options.

  • Nasal Decongestants work in a similar way to the oral form of this medication, opening up the nasal passages for easier breathing. The difference, though, is that these are not safe for long-term use. Experts warn patients not to use a nasal decongestant for more than a few days since longer-term use can cause a rebound effect, which can cause you to become even more congested when you stop using the medicine. Other side effects to be on the lookout for include excess dryness and burning in your nose. Popular nasal decongestants are ones like Afrin® (nasal spray), Vicks®, Sinex®, Neo Synephrine and Dristan®.

  • Decongestant Eye Drops can be found as a stand-alone treatment option or can also be combined with an antihistamine. This form of medication treats red, itchy and irritated eye symptoms. This is generally safe but overuse can damage the blood vessels or cause increased redness. Popular options are available over-the-counter and include Visine® and Murine®, among others.

Other Options

    In addition to the general medication categories listed above, there are also a few new options available today that can be effective for treating allergy symptoms.

  • Leukotriene Modifiers, like Singulair®, are prescription drugs available in pill and tablet form that block the chemical called leukotriene that is formed in your immune system when you are exposed to allergy triggers. This type of medication can be effective in reducing hay fever symptoms and also in treating asthma. Possible side effects include tiredness, headaches and dizziness.

  • Cromolyn Sodium can be found in both nasal spray and eye drop form without a prescription. This formulation is effective in blocking histamine, a chemical that also causes a range of allergy symptoms. What makes this medication different from an antihistamine, whether administered through the eyes of nose, is that it should be used before the symptoms occur as a way to prevent them from kicking in. A variety of possible side effects can occur and this can differ depending on the medication you choose. Types you can find include NasalCrom, Crolom and Alamast®.