Allergy medications are over-the-counter and prescription drugs designed either to prevent or to treat the symptoms of an allergic reaction. Most of these treatments belong to one of four classifications:

• Antihistamines
• Decongestants
• Anti-inflammatories
• Bronchodilators

Allergy drugs come in many different forms, including pills, nasal sprays and creams. Some are to be taken after symptoms appear, while others are taken regularly to prevent future reactions.

These medications all have potential side effects and may not be suitable for people with certain existing medical conditions. As with any drug, consult a physician before taking allergy medications, whether they are prescription or over-the-counter.