weigh in. Be weighed; also, be of a particular weight. For example, Because it was such a small plane, the passengers and their luggage had to weigh in before takeoff , or The fish weighed in at 18 pounds. [Late 1800s] See also: weigh.
Asthma and allergic diseases, such as allergic rhinitis (hay fever), food allergy, and atopic dermatitis (eczema), are common for all age groups in the United States.
Types of Allergies. An allergy occurs when your bodyâs immune system sees a certain substance as harmful. It reacts by causing an allergic reaction. Substances that cause allergic reactions are allergens. There are many types of allergies. Some allergies are seasonal and others are year-round. Some allergies may be life-long. It is important to work with your health care provider to create a plan to manage your allergy. Avoiding your allergens is the best way to prevent an allergic reaction.