Farmer's lung is an allergic reaction to hay dust or mold spores or other agricultural products. However, dust from any moldy crop - straw, corn, silage, grain, or even tobacco - can also cause Farmer's Lung. Individuals may develop inflammation which may progress to a potentially dangerous condition. The disease is most common in regions with wet weather at harvest time. Farmer's lung is also more common on dairy farms, especially those not equipped with automated equipment for handling hay or feed. Attacks of farmer's lung occur most often in late winter or early spring when stored hay or grain is used to feed livestock. For people suffering from acute attacks of farmer's lung, the first step in treatment is to avoid further contact with moldy dust. For serious cases, bed rest is recommended and oxygen therapy may be needed to relieve shortness of breath. Certain medications provide relief from an allergic response during acute attacks and make breathing easier. The long-term use of these drugs is not advisable since they can hide the symptoms of farmer's lung without preventing lung damage from re-exposure to moldy dust. No cure exists for people who become hypersensitive to moldy dust. Once people become hypersensitive, they remain hypersensitive for years, perhaps for life.