Typical causes of low oxygen levels include chronic obstructive pulmonary disease, a blocked airway, anemia, congenital heart disease, and medication such as anesthetics and narcotics, according to Mayo Clinic. Low oxygen levels, also called hypoxemia, are a common cause of hypoxia, a condition in which the blood carries an insufficient amount of oxygen to the body tissues.
For the body to function properly, a certain amount of oxygen has to circulate in the blood to the cells and tissues. Heart problems, a decreased red blood cell count, and lung conditions such as fluid in the lungs, bronchitis and chronic obstructive pulmonary disease are common causes of low oxygen levels, states WebMD.
Decreased oxygen in the brain can occur from carbon monoxide poisoning and brain injury, causing adverse effects, as the brain cells require an uninterrupted flow of oxygen for their functions. Other causes include extremely low blood pressure, irregular heartbeats, traveling to high altitudes and asthma, notes Healthline. Asthma narrows airways, preventing enough air to reach the lungs.
Symptoms vary from person to person, but typical symptoms include rapid breathing, shortness of breath, sweating and fast heart rate. Coughing uses oxygen, causing the symptoms to worsen. Patients should be aware of their asthma triggers and avoid them, emphasizes WebMD.