Perennial rye allergy is an immune system reaction to pollen from perennial ryegrass. This common grass grows year-round in many climates and releases pollen that triggers allergic responses. When you breathe in perennial rye pollen, your immune system mistakes it for a harmful invader. Your body then produces antibodies called immunoglobulin G, or IgG, to fight off the perceived threat.
This type of allergy falls under the broader category of grass pollen allergies. Perennial ryegrass is often used in lawns, parks, and athletic fields because it grows quickly and stays green. That widespread use means many people encounter its pollen regularly. Unlike seasonal allergies that come and go, perennial rye can cause symptoms throughout much of the year in mild climates.
Grass pollen allergies affect about 20% of adults in the United States. Many people with perennial rye allergy also react to other grass types. Understanding your specific triggers helps you take steps to reduce exposure and manage symptoms more effectively.