While often annoying, coughing serves an important protective function. This defensive reflex clears the airways of excessive mucus and potentially harmful germs and particles. A short-term cough that accompanies a cold or the flu typically lasts no longer than 3 weeks. A persistent or recurring cough often signals a more serious medical condition. Although coughing usually isn't harmful in and of itself, vigorous attacks can sometimes lead to dangerous complications. These complications occur most often in vulnerable persons, particularly infants and seniors.
Broken ribs (rib fractures) represent the most commonly documented complication of cough, as noted in a November 2006 article published in the "World Journal of Emergency Surgery." This complication most often occurs in older adults with a chronic cough and affects women more often than men. Underlying loss of bone mass or osteoporosis increases the risk for cough-induced rib fractures. Although rare, broken ribs caused by vigorous coughing can potentially puncture a lung, cause bleeding within the chest, or pierce the diaphragm, the muscle that separates the chest and abdominal cavities. These rare but dangerous complications of cough-related rib fractures require immediate medical evaluation and treatment.
An episode of severe coughing sometimes leads to fainting, a complication known as cough syncope. Although the exact mechanisms involved in cough syncope remain incompletely understood, reduced blood flow to the brain during a coughing attack is likely a key factor. Fainting associated with coughing can potentially lead to dangerous accidents or falls. Some preexisting conditions increase the risk for cough-induced fainting, including:
- Chronic obstructive pulmonary disease (COPD)
- Whooping cough
- Cystic fibrosis
- Certain types of heart rhythm abnormalities
- Gastroesophageal reflux disease (GERD)
- Brain tumors and excess fluid around the brain (hydrocephalus)
Abdominal Muscle Tears and Hernias
Vigorous coughing induces extreme, rapidly changing pressure in both the abdominal and chest cavities. This sometimes leads to tears in the abdominal muscles, particularly the paired rectus abdominis muscles that run vertically along either side of the navel. Typical symptoms include sudden pain that worsens with subsequent coughing, sneezing, laughing and lifting. Although rare, coughing might cause a complete rectus tear that allows the intestines to protrude through the abdominal wall -- an abdominal wall hernia. Depending on the size and severity of the hernia, surgical repair might be necessary.
Prolonged, vigorous coughing can potentially interfere with gas exchange in the lungs and lead to reduced oxygen delivery to the body tissues. The brain is particularly susceptible to the damaging effects of oxygen deprivation, also known as hypoxia. Cough-related hypoxia most frequently occurs in babies with whooping cough, also known as pertussis. Compared to older children and adults, babies with pertussis are at increased risk for becoming hypoxic during coughing attacks and might temporarily stop breathing after a coughing episode. Infants with whooping cough are also at increased risk for developing bacterial pneumonia as a complication of the illness, which puts them at further risk for brain hypoxia. Hospitalization with possible temporary placement on a ventilator is sometimes needed for infants with severe whooping cough, particularly if the baby is younger than 6 months.
Vigorous coughing can lead to other complications of varying severity that might pose a health threat in certain circumstances. These include:
- Cough-induced urine leakage
- Rupture of tiny capillaries in the face or whites of the eyes
- Feeding difficulties, gagging or vomiting, particularly in young children
- Physical exhaustion
- Sleep disruption
- Social isolation and/or depression
Next Steps, Warnings and Precautions
See your doctor as soon as possible if you have an unexplained cough that persists for longer than 3 weeks. Seek urgent medical care if you experience a cough accompanied by warning signs or symptoms that might indicate a serious complication or underlying condition, including:
- Difficulty breathing, shortness of breath or inability to catch your breath
- Chest pain, or racing or irregular heartbeat
- New or worsening abdominal pain or bulge
- Fever, chills or excessive sweating
Reviewed and revised by: Tina M. St. John, M.D.
- World Journal of Emergency Surgery: Cough Induced Rib Fracture, Rupture of the Diaphragm and Abdominal Herniation
- Comprehensive Pediatric Hospital Medicine; Lisa B. Zaoutis and Vincent W. Chiang
- Mayo Clinic Proceedings: Cough-Induced Rib Fractures
- Respiratory Medicine: Cough Syncope
- Murray and Nadel's Textbook of Respiratory Medicine, 5th Edition; Robert Mason, et al.