A flexor reflex, which is also called a withdrawal reflex, is a multisynaptic reflex. It is a type of protective reflex where a painful stimulus triggers the contraction of flexor muscles. These reflexes have a slower onset and a longer response than the stretch (extensor) reflexes. A flexor reflex requires the contraction of a flexor muscle and relaxation of the extensor muscle in that limb. A good example of a flexor reflex is when you touch your forearm to the side of a hot oven.
Causes of Hypoxia. A severe asthma attack, or flare, can cause hypoxia in adults and kids. During an attack, your airways narrow, making it hard to get air into your lungs. Coughing to clear your lungs uses even more oxygen and can make symptoms worse. Other things can cause hypoxia, too: 1  Lung diseases such as chronic obstructive pulmonary disease (COPD), emphysema, bronchitis, and pulmonary edema (fluid in the lungs). 2  Strong pain medicines and other drugs that hold back breathing.
Causes of Hypoxia listed in Disease Database: Other medical conditions listed in the Disease Database as possible causes of Hypoxia as a symptom include: Acute lung syndrome. Asthma. Atrial septal defect (ostium primum) Bronchiectasis. Bronchiolitis. Bronchiolitis obliterans. Bronchiolitis obliterans organizing pneumonia.