Intravenous injections are a medical procedure used to deliver fluids, medications, or nutrients directly into a person's bloodstream through a vein. This method allows for rapid absorption and immediate effects, making it useful in emergencies or for patients who cannot take medications orally. The procedure typically involves inserting a thin needle or catheter into a vein, often in the arm or hand. Once in place, the healthcare provider can administer the required substance, monitor the patient's response, and adjust the dosage as needed. This technique is commonly used in hospitals and clinics for various treatments.