Inhaled

Inhaled refers to anything drawn into the lungs through the act of breathing, or to substances delivered to the body via this route. The term commonly describes gases, aerosols, or particulates that enter the respiratory tract and reach the airways or alveoli. Inhaled substances can have local effects in the lungs or systemic effects when absorbed through the alveolar surface.

In medicine, inhalation is a route of drug delivery used for both local and systemic purposes. Local therapy targets the airways and lungs, as with inhaled bronchodilators and corticosteroids for asthma or chronic obstructive pulmonary disease. Systemic effects are possible when drugs are formulated for rapid absorption across the alveolar membrane, providing quick onset with reduced first-pass metabolism. Delivery devices include pressurized metered-dose inhalers, dry powder inhalers, soft mist inhalers, and nebulizers, which vary in technique, particle size, and dosage form.

Pharmacokinetics and deposition are influenced by particle size, airflow, and breathing technique. Smaller particles reach deeper into the lungs, while larger particles deposit in the oropharynx. Inhaled medications can provide rapid relief or sustained control, but improper technique can reduce efficacy and increase local irritation or systemic side effects.

Safety and exposure considerations include risks from inhaled toxins, smoke, or industrial fumes, which can cause acute or chronic respiratory harm. Proper device use, inhalation technique, and protective measures are essential in clinical settings and occupational environments.