Adult attention-deficit/hyperactivity disorder, commonly known as adult ADHD, is a mental health condition characterized by a persistent pattern of inattention, impulsivity and restlessness. Although often associated with childhood, ADHD begins early in life and may continue into adulthood. In many individuals, symptoms are not recognized or formally diagnosed until adult years. Adult ADHD can affect many areas of daily life, …

Atypical hyperplasia of the breast refers to the growth of abnormal, precancerous cells within breast tissue. In this condition, breast cells increase in number and show changes in their appearance when examined under a microscope, making them look different from normal breast cells. Atypical hyperplasia is not breast cancer. However, it is an important warning sign because it is linked …

An atrial septal defect, often called ASD, is a heart condition present at birth. It is a type of congenital heart defect in which there is a hole in the wall that separates the two upper chambers of the heart, known as the atria. This opening allows oxygen-rich blood from the left atrium to mix with oxygen-poor blood in the …

Avascular necrosis is a condition in which bone tissue dies because it does not receive enough blood. It is also known as osteonecrosis. When blood flow to a bone is reduced or stopped, tiny breaks can form in the bone structure, eventually causing the bone to weaken and collapse. This process may take months or even years to develop. An …

Aspergillosis is an infection caused by a mold known as aspergillus, which is a type of fungus commonly found in the environment. The illnesses caused by aspergillosis usually affect the respiratory system, though symptoms and severity can vary widely. Some forms are mild, while others can be life-threatening. Aspergillus mold is found both indoors and outdoors. Most strains are harmless …

Asthma is a long-term condition in which the airways of the lungs become inflamed, narrow and swollen, and may produce extra mucus. These changes make breathing difficult and can lead to coughing, wheezing and shortness of breath. For some people, asthma causes only mild and occasional symptoms. For others, it can be a serious condition that interferes with daily activities …

An asthma attack is a sudden worsening of asthma symptoms. Asthma is a long-term condition that affects the airways in the lungs, causing them to become narrow and making breathing difficult. During an asthma attack, symptoms such as coughing, wheezing, chest tightness and trouble getting enough air can develop or rapidly worsen. These symptoms occur because the muscles around the …

Asthma is a long-term (chronic) lung disease that affects your airways. Your airways are the tubes that carry air in and out of your lungs. When you have asthma, you can’t get air into your lungs because your airways swell and get too narrow. Like a pinched straw, this makes it hard for you to breathe, which can cause wheezing, coughing and chest …

Exercise-induced asthma, also known as exercise-induced bronchoconstriction, is a condition in which physical activity triggers narrowing of the airways, making breathing difficult. It can occur in people with or without chronic asthma and is commonly triggered by vigorous exercise, especially in cold or dry air. Symptoms usually begin during exercise or shortly after stopping and can interfere with physical performance …

Occupational asthma is a type of asthma that is caused or worsened by exposure to substances in the workplace. It occurs when inhaling certain chemicals, dusts, fumes, or biological agents triggers airway inflammation and narrowing. Symptoms may improve away from work and worsen during working hours, making early recognition and intervention important to prevent long-term lung damage. Symptoms Symptoms of …