More than 50 million people in the United States suffer from asthma and allergies. Fortunately, today there are many effective medications available to treat these conditions. The most common categories of drugs used to treat asthma or allergies include: antihistamines, decongestants, anti-inflammatory agents (such as corticosteroids), anti-leukotrienes and bronchodilators. Read more about these drugs by visiting the links below.